Wanting to play something other then a warrior, I want to try a Dunmer Assassin. To do this, I will use One Handed, Light Armor, Sneak, Archery, Illusion, Alteration, Alchemy, and maybe Pocketpicking as my skills. To make each of my skills efficient, I've figured which perks to take and which not to.

One Handed - Armsman (5), Dual Fury (2), and Dual Savagery.

Light Armor - 0 Due to the fact, I'll be sneaking the whole time and I'll be using Alteration spells to boost up my armor rating.

Sneak - Max of every perk.

Archery - Overdraw (5), Eagle Eye, Steady Hand (2), and maybe Power Shot (could use poisons to paralyze).

Illusion - Novice, Animage, Apprentice. Kindred Mage, Adept, and Quiet Casting.

Alteration - Novice , Apprentice ,Magic Resistance (3), Adept, and Stability.

Alchemy - Alchemist (5), Physician, Poisoner, Concentrated Poison, Green Thumb, and Snakeblood.

Pocketpicking - Light Fingers (5), Night Thief, and Poisoned

Now with the perks out of the way, I need to figure out how to distribute stats. This is were you guys come in along with advice and tweaking of my build.

I've played with a Dunmer assassin for quite some time at expert difficulty. As you progress you'll find that pickpocket and illusion are obsolete, since you'll one shot most people with the bow, and those that you can't you just go for the backstab on. Alchemy is useful, primarily for invisibility potions, and one handed is pretty vital. I didn't try alteration on my Dunmer, but I wouldn't recommend it. Just focus on light armor, it is too inconvenient to have to recast armor spells over and over again and better skill in light armor will be superior to anything you can get with alteration. Either way, if you do it right, you won't be getting hit much if at all. Smithing and enchanting are unnecessary since you'll be killing in one or two hits with the sneak multiplier anyways. Arguably the coolest set of armor for an assassin is the and it's heavy armor, which was sort of a disappointment but by the time I got it at like level 30 I had been hit so few times it didn't really matter that I used it along with my other light armor. Eventually I ditched the light armor for clothing, because I just wasn't getting hit. You'll need armor for early game though. Anyways, there's some advice from someone who's been around the block. Try the Dark Brotherhood questline, it's one of the best if not the best in the game.

Hmm taking out Alteration and Illusion would allow me to focus on health and stamina. Pickpocketing is only for the skill to harm people by putting poison in there pocket, but I don't think it's worth putting points into. For Light Armor, do you think I should get perks for it or keep it the way I have it?

Bump

I have been looking into the same thing. The thing I found in my research is that you can get to the armor cap (567) with light armor by spending 3 to 5 points while Alteration will require a minimum of 5 plus an investment in Magika. In addition the spell that gets you to cap, Dragonhide, only lasts 45 seconds with the stability perk.

For all characters, you have to pick an attack and a defense. Let me tell you: archery is the bomb. One-handed is for spice, variety, etc. But when you have to do business, archery is going to be 98% of your attack work if you are being efficient. And your defense is going to be sneak. Max those. The best complement to those is enchanting. Take that up all the way, and you can put two enchantments on items. So I have my ring of sneaking+archery, my necklace of sneaking+archery, and other dual enchanted items. Like bows of paralysis and soul trap, or bows of frost and lightning.

But I like one-shotting giants and two-shotting mammoths.

Personally i love using illusion because with the right equips its possible to have 100% illusion cost reduction which means nonstop invisibility and muffle enchantment.
This is the only reason why my mage with crap sneak and pick pocket was able to do all the thief sneak missions and get away with a bunch of Dark brotherhood nonsense.

Dropping Alteration and Illusion would be a good idea. Using those schools effectively requires a significant perk investment, dedicated enchants, and lots of Magicka.

I also wouldn't perk One Handed. As Atomic Tank mentioned, sniping as an Archer is extremely effective, so there's little reason to spend another ~10 perk points in One Handed simply to give yourself a max-damage melee alternative. The backstab perks + Shadow Warrior in Sneak along with the DB gloves will allow you effectively use daggers with minimal perk investment already.

I'd recommend spending 2 points in Smithing (Steel, Elven), 8 points in Enchanting (5/5 Enchanter, Insightful Enchanter, Corpus Enchanter, Extra Effect), and 3 points in Light Armor (1/5 Agile Defender, Custom Fit, Matching Set). You can easily craft a DR and MR capped set of Elven armor that weighs only 7 lbs total. Perfect for a sneaky archer. Getting your Light Armor skill to 100 can be tedious (that's what training is for), but you'll at least have that option if you want to play on Expert or Master.

Try something like http://skyrimcalculator.com/#28152 as a base. After that, you can perk whatever strikes your fancy. A few points in Restoration is always well spent, and Pickpocket is lots of fun for a sneaky character (not to mention Extra Pockets is very useful).

In my Assassin builds, I have whittled my necessary Skills down to a small list of five. By focusing on these, I am nuking most everything that I come across. I kill at will, and the five Skills I have focused on are;

1) Sneak: Obviously, once you get Sneak at/near 80, most every enemy except Dragons will not notice you unless you walk right in front of them, and even that is possible if the shadows are right... Also 15x's Sneak attack damage with dual wielding daggers (30x's damage with the Shrouded Gloves equipped)

2) One-handed: For the Daggers... it's all about the daggers.

3) Archery: Once you get some perks into Sneak and Marksman, you can pretty much one-shot anything that moves. The cost in Perks pays for itself in results.

4) Light Armor: Get up to the Matching Set Perk and a couple others, wear the Shrouded Armor (full set), and it won't really matter if you have to have a stand-up fight. Your Armor Rating will grease you through even the battles when you do happen to get deteted...

5) Smithing: Lets you keep on top of the best weapons (Daggers and Bows) for the ratio of your level to enemy level.

I really only use these five. I don't use the following because of reasons below:

1) Illusion: The whole Perk tree for Sneak makes this School obsolete. Again, get your Sneak skill to about 80, and Illusion won't matter anymore. Don't waste your Perks.

2) Lockpicking: The lockpicking mini-game is easy enough that I was picking Master level locks with a Skill score of 20. The Perks help grease it, but seeing all of the better areas to apply those Perk points, and with your Skill Level being enough to slide you past 90% of the locks that you come across, it just seems silly to apply Perks into this skill.

3) Alteration: Worthless for an Assassin. If you are getting discovered enough that you have to cast Oakskin that many times, then you should probably pick another career option for your character...

4) Alchemy: Is equally pointless for an Assassin. Yes, you can create poisons, but by the time you can create the really useful poisons, your base damage from One-handed + Sneak + Weapon-type is enough to drop most any enemy without the use of poisons. Again, wasted Perks.

5) Pickpocket: Why bother? Just loot their corpse after you Sneak attack them or one-shot them... for the enemies that you can't kill (i.e. essential NPC's), just like Lockpicking, your base Pickpocketing Skill Rank is more than enough to grease most pickpocket attempts. Don't waste the Perks.

The only Skill that I didn't put on my list above is Enchanting. I really only apply Perks into this Skill Tree when I don't quite have enough Skill levels to apply the point into any of my preferred five Skills. Even then, i only create enchanted bows. Makes Dragons much less pesky...

Mix all of my Skill choices with the 'Marked for Death' Shout, and there is nothing on Nirn that will be able to withstand you.

The above lists and reasons are all my opinion, and based off of experiences I've personally had whilst playing nothing but Assassin characters. This is what I've found works best for me, and makes me really not care what I come across, because I'm almost guaranteed to kill it in less than a minute.

As far as Armor, the Ebony Mail is nice, but I much prefer the Shrouded Armor/Ancient Shrouded Armor. The abilities (if not the Armor rating) are far more diverse and useable in my opinion. The Armor Rating for the Ebony Mail is superior to the ASA, but if I need to rely on my Armor rating that much, then I really need to work on my lacking Sneak Skill... So I always go with the Ancient Shrouded Armor.

Hope all of this helps.

Theres a enchantment for damage resistance? Also whats the point of armor, when I'll being one or two shotting everything? The only thing I could think of it being useful, is if a dragon attacked. If a dragon does attack, do I just use my bow to take it out?

Not really; just Fortify Light/ Heavy Armor enchants, which you won't need. Capping DR comes simply from properly crafting your armor. Capping your MR comes from a variety of sources, but unless you're a Breton, you'll likely have to use at least one Resist Magic enchant to hit the 85% cap.


My recommendations assumed you were playing on a challenging difficulty setting. If you're going to faceroll through the game on Adept with godlike weapons, it probably won't matter how you build your class. Though even with uber-weapons, you'll want to be DR and MR capped on Expert and Master. Otherwise, Ebony Bow-wielding Draugr Deathlords and air-borne Ancient Dragons can and will one-shot you.

I'll try it tonight, thanks.

Dubious plan. Until you get 50 points in Illusion, you'll constantly be giving yourself away by casting the 'skin spells, or just wasting half their duration by casting out of earshot and then sneaking close.

The 'Throw Voice' shout is massively useful for a Thief/Assassin, especially for distracting guards so you can escape or for luring them away from whatever they're guarding.

Putting 1 or 2 points in the first Sneak tree is more than enough, you don't need 5.
I have 1 point in there on my assassin and combined with the DB / Thieves / Cicero armor enchant that makes you muffled, you're nearly undetectable unless you're in the sunlight.

So that leaves 4 perks to be spent somewhere else.
I personally didn't perk into archery since I hate the aiming with it on a PS3 (It's not bad, but when you're doing the Stormcloak/Imperial questline and attack a Fort, I swear I miss 85 out of 100 arrows I shoot because of my "allies")
So I perked more into one-handed and smithing.

Alchemy / poisons aren't really worth it as you can pretty much one-shot everything except dragons. I like to poison my bow with a weakness to fire and then deal some blows with my fire enchanted blade (I went blades for when I do have face-to-face combat)

Yeah, enchanting isn't really needed as the enchants on DB/Nightingales/Cicero are good enough, and let's be honest here, there's nothing that beats the Jester armor in a looking-good competition.

As said by others, alteration and illusion aren't really worth it unless you're into some WoW-Roguelike vanishing sort of thing.

That's just my opinion though.

1. Illusion perks: quiet casting, novice- expert illusion. 7 perks.
2. Sneak perks: everything except shadow warrior (waste of a perk once invisibility is set up) 8 perks.
3. Muffle boots.
4. About 260 mana (through rings or necklaces or whatever) for using multiple casts in battle against multiple opponents.
5. Invisibility spell.
6. DB gloves.

Once you have the above, all you will need is a steel dagger... for any difficulty.

The only problem you will have.. is what to do with the perks after level 30. Since this attack form is so quick and powerful, nothing stands out. Even enchanting seems pointless since the ring and neck slots aren't even needed to buff anything except maybe mana or health.

Enjoy running through dungeons constantly invisible, dropping into sneak mode in front of enemies that can't see or hear you. Cutting them to shreds, and disappearing a half second later.

@Udey: But Illusion is completely pointless if you have your Sneak high enough to get the perk for Running/Walking. Your Sneak is so high, plus with the DB/TG/NG Armors, no one should see you unless you make a drastic escape. So I can save you 7 Perk points there.

Why waste the time grinding out Illusion, when it can be put somewhere else more beneficial? Having Sneak and Illusion is an unnecessary redundancy and a waste of Perk points.

There is no reason to raise the first SNEAK perk above 1 with the other perks and easily available sneak related armor. It's a waste of 4 perks. I think ignoring the LIGHT ARMOR perks is a mistake as well, but there are instances when you WILL get hit and wish you had a decent AR.

Unfortunately many people post on this issue without trying it first.
I can pull up about a dozen threads where posts like your above has been shot down because it is uninformed.
hint: search "assassin" and "illusion" you have some reading/testing to do.

I will leave it at:

1. You are wrong.
2. invisibility is totally different from sneak.
3. Obviously sneak + invisibility is going to be much stronger because of synergy.
4. Invisibility can break combat in an instant, and rob enemies of 1/3 of their detecting ability- that of sight. Shadow warrior is a poor mans invisible. If you played DnD- properly perked invisible functions as "hide in plain sight."
5. No need to retreat with invisibility. Combat breakage makes it tons better than sneak. Gotta love running away as a sneaker. Not needed with my suggestion.

But I have grown tired of constantly defending this issue, so whatever. If the OP tries it my way, he will be impressed.

Whenever I try to go invisible to hide it does absolutely nothing most of the time :/

@ Buhry. You will need the silent casting perk to repeat cast invisibility (this perk needs to be stressed). Also the spell it does not stand on its own as a hiding method (much to the chagrin of mages), rather is eliminates a method of detection for enemies.

So alone it does not function well, since if you have no sneak skills/perks they will hear you anyways. But! if you do have said perks/sneak skill and muffle boots then you cannot be directly detected by sound, and invisibility will instantly break combat (since they could only see you before, and now they cannot.) The only way for them to re-find you is you touching them.
Enemies detect by:
1. Touch.
2. Sound.
3. Line of Sight.

Invisibility turns off number 3. Sneak alone cannot.

--This leads to amusing situations of repeat throatcut kills that happen as fast as you can cast invisibility when swarmed, all without taking a hit --

It is tricky to get everything in order, and get the hang of it (which is why we have a bunch of people who cry about it being worthless) but once you understand how to use it, and have all the requirements... It will make sneak alone seem like babytown frolics, and you will never want to go back.

Stuff I picked up along the way as both a thieve and an assassin:

1. Get the mask of Krosis if you plan on using a bow as your main weapon. It gives a 20% bonus each to Archery, Alchemy and Lockpicking. Korsis is at Shearpoint just east of Whiterun.

2. Pickpocketing may seem like a useless skill. It's not for three reasons. Free training in all you skills and fun. When you get to the point where you have to pay 4K for 1 lvl of training you'll be glad you can just steal your money right back from the trainer. And stealing someones armor / clothes right of their back before stabbing them never gets old. The Deep Pockets perk increases your carry capasity with 100 points. That means more time in dungeons and less time selling junk to free some space.

3. Illusion is very useful in situations where you have to eliminate groups of people like foresworn camps or hagrave dens. You can use rage spells to make them wipe each other out and just round up the straggelers if any are left. You can use a calm spell on the guy pounding your face in because your backstab / sneak shot didn't quite go as planned and then stab / shoot him again. Or you can vanish from sight all together. This is especially usefull in the woods if you bump into an ice troll or some such unexpectedly.

4. Lockpicking sounds useless as well but there is a one reason why you could put at least some points in it. Treasure Hunter. This perk will give you a much better chance of finding rare / more powerfull loot in locked chests. You'll most likely not get into smithing so this at least will give you a better chance to get that daedric bow. And of course more loot to sell is always good. It's not essential though.

5. Alchemy is not only useful for poisons. Like some have said poisons are a bit of an overkill later in the game although I find that on expert you only one shot much lower enemies with a bow. However, it does allow you to create health / magic / stamina potions, various restistence potions (fire, frost, lightning, magic, poison etc.), invisibility potions (especially usefull if you don't use illusion) and skill boosting potions (one handed, archery etc.). Again, not essential but I figure since you'll be sneaking all over you might as well put all those ingredients to good use that you pick up.

6. Archery. If you like the sniper style of play like I do then this one is an obvious must. However, there are a few perks here that you won't even miss. Steady Hand sounds good. It slows down time when you zoom in on a target. Unfortunately it's not really as cool as it sounds. It does what it says but the catch is it slows down everything, not just your target. So it's just a slow motion version of what you would normally do. If you can't hit a target at normal speed when zooming in, chances are you can't hit him while in slow time. Rather just practise your timing. Hunter's Dicipline is a total waste. The world is full of arrows and they even got them in the shops. Ranger is also useless as you won't often run after enemies with a drawn bow trying to shoot them. Bulls Eye can also be ignored. 15% chance to paralyse a target? Meh, even if your target is still alive and it procs it only makes it harder to get a second shot.

That's all I can think of for now. The key is to be patient, observant and don't hesitate to run away screaming like a little girl if you land in the fire.

1. Illusion - Completely disagree with those who say illusion is pointless for an assassin build. At low levels the calm/fury spells can be lifesavers in situations you can't sneak out of and muffle is quite useful as well. You can also use muffle to boost your illusion skill to 75, so you can get invisibility. Once you have a high sneak skill, invisibility, quiet casting and either of the armors you get later on in the TG/DB quests, you'd be unlucky if you get it at all.
2. Sneak - Don't need to explain this.
3. One-Handed - More important than archery IMO, because it doesn't alert other opponents when you backstab someone and with a good dagger and x15/x30 sneak attack bonus most enemies become one hit kills.
4. Archery - Ranged option, useful against dragons and for sniping enemies.
5. Light Armor - Levels fairly quickly early/mid game when you can't one hit kill everything and gives you a better armor rating than alteration spells, as well as allowing extra magicka for illusion. Gives a very good defensive rating with one of the armors i mentioned.

My first character was a dunmer assassin and if i were to do it again these are the skills/perk trees i would focus on. I tried to also focus on destruction and alchemy, but these became pointless as my character progressed. Finally i would invest in some restoration perks for healing/magicka regeneration.

I'll start with the perks and then go to what I personally used for my stat boosts... This is also based on nearly 200 hours of play and and I'm now level 81 but I will only go through what I use for assassination here instead of my complete Jack of All Trades style build... Also I play on Master difficulty and still have the ability to one shot Giants and even took out an Ancient Dragon on Master with my pair of Daedric Daggers (Legendary though far beyond the normal legendary level) doing 112 damage each with all my perks and a pair of shrouded gloves (total base damage out of this is 6720)...

First of all in the One Handed perks there's another that can be useful but you don't technically need, it's called Fighting Stance and will reduce the cost of your power attacks with one handed weapons by 25%

Light Armor- I recommend simply because no matter how good you are there's always a chance that you will have to fight things without the aid of sneaking around, but I only took the all of the perks EXCEPT Deft Movement, I simply don't want to rely on luck to save my skin once in a while...

Sneak- First of all I manage to sneak by anything just fine with only the first rank in the Stealth perk so I find the extra ranks in it useless which saves you 4 extra perk points you can better place elsewhere... Take the backstabbing branch all the way up to Assassins Blade for the 15x sneak attack damage with daggers... Deadly aim has its uses too since there are times you will want to use a bow to kill your enemy from afar however it isn't nearly as deadly as your daggers so use those if at all possible... Now for the other branch, Muffled Movement is only necessary because it's required for Light Foot, which is one of the more useful stealth perks but I personally won't go past it since I've got no use for Silent Roll and once you have an enchanting ability Silence will also be obsolete (Until you have a Muffle enchantment on your boots you can just use the spell of the same name and not have an issue as long as you have Quiet Casting but more on that when we get there) with the proper gear and spells...

Archery- All ranks of Overdraw are a must for ranged sneak attacks since your bow won't come close to the daggers and only gets a 3x sneak attack bonus... Critical shot isn't that good unless you want to rely on luck and as an assassin that's usually not the best idea so I would avoid it unless you want perks that require you to have it... Eagle Eye will allow you to easier take out targets from a safer distance so it's another excellent skill to have... Steady Hand has it's uses but I only use it when fighting dragons so you don't have to have it... Power Shot is actually useful since it's percentage is 50% and I find it comes in handy but mainly only has use on assassinations where you take out an enemy where there is noone that can witness it anyway so it's not required... Quick Shot is also good but is another one where you'll only get any real use out of it when fighting dragons or when you can't kill the enemy in a single shot... And Bullseye is another luck based perk that I have but is only useful if you get lucky with a shot that doesn't kill the enemy so it's another one that's not necessary...

Illusion- Those who play assassins that overlook this tree are foolish in my honest opinion, 1 main reason INVISIBILITY... First of all take all the spell level perks through Expert but not to Master... None of the Master level spells are that useful unless you have ALL of the Illusion perks and if you need to cast Harmony you've done something extremely wrong and also unless you have some serious casting cost enchantments on your armor for Illusion magic then it's going to cost more mana than you are likely to have at any given time unless you focus relatively heavily in it... At 100 Illusion with all perks up to expert the Invisibility spell will cost you 99 mana to use and with the armor setup like I've got with -28% casting cost for Illusion it only costs me ~73 mana... Muffle is good until you get the Enchantment on your boots... For the other perks go all the way up to quiet casting through the Kindred Mage and Animage perks and I also have Master of the Mind and find it useful but much less so than the other perks I've listed... None of the calm, frenzy or fear spells have any worthwhile use as an assassin because, as I've mentioned previously, if you have a need for them you've done something wrong (though I will admit that Mayhem can be quite entertaining at times to cause some serious chaos)... Muffle is also, for some odd reason, the fastest way to raise your Illusion skill to max or at least high enough to use invisibility but at some point you will want to max it if for nothing else but the reduced casting cost of your spells that comes from the higher levels in the skill...

Alteration- I find that this school, while it does have its uses, has no requirement for perks in it since there are only three spells in it that I've found to be truly useful (Candle Light, Mage Light and Telekinesis) and I have and have tested every single spell in the game but I don't have perks in all the skills because I found them to not be very useful... As far as the three spells go Candle Light is useful for lighting your way when you have a need for it but you won't want to use it often since for assassinations only the Falmer won't see you with it up as they are blind, for Mage Light it's the same basic concept but it doesn't follow you around and instead it goes where you aim the spell, Telekinesis on the other hand is the only of these three spells that costs much mana but you'll pretty much only use it for disabling traps before you get to them or picking up items from trapped objects so you won't need to worry about its high cost... Detect Life and Detect Undead can also be extremely useful at times when planing your path before making your kill but again you won't need to use them for very long and with quiet casting you don't have to worry about your distance from the enemies too much...

Alchemy- While Alchemy has its uses I don't find the perks in it to be that useful since the only thing I've ever made with it that I used were a couple of invisibility potions for the times when the spell isn't fast enough for my needs, and these times are few and far between... If you find that you still want to use it for poisons that's up to you but I would recommend the Purity perk when you hit 100 in the skill so you don't give any of your opponents any bonuses with the poisons or yourself any negatives out of the potions...

Pickpocketing- The only perks in this I've actually gotten much use out of aren't really assassin based but Stealing people's weapons an armor off of them before you stab them can be quite entertaining but you still have to find a Fence to sell the armor too unless you have a high level of Speechcraft with the right perks... Poisoned could have it's uses but I've never actually found it to be worth it, but then again I also prefer the more personal feel of a knife in the back when killing stealthily so if you want it take it but otherwise I'd just leave it out... And for the rest of the perks Extra Pockets is good for anyone and you don't need 5 ranks in Light Fingers to steal most things and pretty much any higer level items that are useful are not going to be obtainable through picking pockets...

Now for other skills that have excellent uses for an assassin...

First of these is Enchanting- Enchanting will allow you to put your own enchantments on your armor and if you take all of the perks from both of the branches on the right side and middle then you will be able to enchant each of your weapons and armor along with your rings and amulets with 2 enchantments each with no penalties thus making you even more powerful... All 5 levels of the Enchanter perk and have enhanced skill enchantments and thus enchant armor pieces with 25% bonuses for smithing without a potion to enhance it and if you buy a potion (Elixir of Enchanting at the highest level for this) to enhance it then you can get this to 28% and thus make your weapons and armor even more powerful... This is how I've got 1025 armor with full Dragon Scale and weapons that do so much damage... Also putting a Muffle enchantment on your boots solves the need for any spell but invisibility for assassination...

Next of these is Smithing and if you are making your own armor you'll want at least up to glass armor though I wear Dragon Scale for aesthetics... Once Smithing is at 100 you can upgrade your weapons and armor to extremely high levels... With all perks my Daedric Daggers do 112 damage each plus enchantments and my Daedric Swords do 250 each with all perks my Daedric Bow is around 225 I believe with all perks but I'm not sure on the bow since I don't use it as often... Smithing is the only way to obtain Daedric weapons in the game as noone carries them and you will definitely WANT them though they aren't required... Unfortunately aside from Arcane Blacksmith as a light armor user who uses weapons as your main source of damage this means you're going to need all perks in this set if you want the best armor you can get though you won't actually need it since you can easily achieve the armor cap which is just below 600 without Dragon Scale armor or even Glass...

Lockpicking- Pretty much a requirement since they've removed the unlock spells from previous games, and you WILL have to break into places if you follow the Dark Brotherhood quest line (besides that who wants to pass up a chest filled with loot because they couldn't pick the lock?), but if you simply invest perk points at each level up to expert and then take Locksmith and Unbreakable you'll have a Skeleton Key in every pick... Quick hands is also good if you want it but wax key is the most useless perk ever since once you've picked the lock I've never seen one become relocked that I would have any need to go back into... Master Locks is useless though since if you take unbreakable you won't have a use for Master level locks to be easier since you'll never break a pick again...

Destruction- Destruction is only useful for some amusemant if you want to use the traps from it but it takes forever to train Destruction and it's not really worth it unless you fancy yourself to be a Wizard style Assassin...

Now for the attributes...

I would recommend 50% of your levels stat increases to go to health and 30% to go into Mana (Magicka) with the last 20% being placed in stamina to be able to power attack more often if you are in real combat (which won't be often, I can clear most dungeons without ever being seen)... Invisibility is expensive but if you have enough mana it will regenerate faster than you will need it out of combat and with quiet casting you can recast it right in front of someone without them noticing you unless it wore off on its own...

For proper use of invisibility when you have to kill multiple targets and want to use it the best way is to have one dagger in your right hand and invisibility prepped in your left hand and already starting to cast (i.e. you have the casting button held down but haven't released the button yet) and don't release the casting button until after the animation for the attack finishes so that it goes off properly, for some reason if you let go of the spell before the attack animation is finished it won't cast either due to a bug or for balance, I don't know which...

Restoration- Though I don't actually see the need to invest perk points into this school of magic it definitely has its uses with healing spells and such...

These are only my opinions based on how I play and my own experiences but I hope they help... Feel free to do as you will with my advice as that is all it is, advice... This is by no means how you have to build your character, it's just how I recommend to do so...