havent run into them anywhere else, but the one at that dragon lair in solsthiem respawns so you can go there after it respawns and ride the serpentine dragon back to skyrim if you want
I'm level 61 and I get mainly Revered and Ancients...only place I always get a Serpentine dragon is Saerin's Watch on Solstheim. On Skyrim I did a few tests, clearing all the Dragon Lairs 2 times and I didn't see a single Serpentine...not even a random one. So, imho, they don't spawn in the mainland
No giants, rebels, forsworn or any of that? Pfft. It's not even a challenge until the game lags from too many enemies.
Oh. I thought you meant just dragons. In that case...
Possible Dragon Priest. 1-2 Draugr Death Overlords. 3 Draugr Deathlord Archers. 4 Draugr Deathlords. 2 Frost Trolls. 12 Skeletons. Plus all possible summons they could have.
Would gladly try but never seen two let alone three. Cant imagine them being a problem.
Arcwind Point always spawn a dragon and a Dragon Den is close enough to attract that dragon as well if you pissed the one off at Arcwind Point first. To get the third dragon, just fly it there and get off.
~Edit~
And trust me. It is a problem if they are Legendary Dragons. That drain shout being tripled will kill you.
It's because you are level 81. You will only get Legendary Dragons or Ancient Dragons, like me.
I've never get any other kind of dragons... Including Revered Dragons. Idky.
Incorrect you can get any level of dragon at level 81, yes you tend to get a lot more Legendary but i have been attacked by all varieties even blood and unnamed ones as well as the serpentine, so i think its to a degree random.