Draugr Deathlord - there's one location outside where there's a swinging log trap, bypass that and DD pops out of his coffin, detects sneak instantly and clobbers you with his ebony axe. ( Arcwind Point?)
That's not a Deathlord. The Draugr Boss at Arcwind is a Draugr Death Overlord, which are among the strongest enemies in game. He is a melee type, not an archer with makes him easy, but there's no room for error.
Note: All judgements rendered on Master Difficulty
1. Chaurus Reaper Queen (Frostfloe Lighthouse)
2. Arch Pyromancer (I've never actually encountered an Electromancer, even though I have well over 500 total hours played in all playthroughs)
3. Draugr Death Overlord (Archer)
Enemies I wish were Harder, and don't do themselves justice.
1. Dwarven Centurion Master. (Seriously, give it like 800 AR, and a "Steam Aura" like the cloak spells. These enemies really deserved to be tougher)
2. Dragons (Too easy to predict, they need a faster, but weaker attack to counter ward 'n' dodge)
3. Dragon Priest (AI is hit-and-miss, sometimes they are pretty mean, other times they just float all stupid-like, if they could be consistently smart, they'd be a nightmare)