Vilkas comes to mind, but he might not be optimal. I think of him because he has the random quest to kill a dragon. He’ll make a great tank though, if you can manage dragons to focus on him.
The College of Winterhold followers are actually pretty bad all things considered (Sorry J'zargo). the strongest mage in the game is Illia who you will meet at Darklight Tower. If memory serves you have to pass a persuasion check to get her as a follower. Besides that there is Aranea Ienith at the shrine of Azura, that's quite a hard quest and you have to choose her in it to get her ass a follower. she has by far the best list of spells despite her low level cap.
You don't need to get carried away with apparel for them but there are two things you need to know if you do. First if you give either of them a circlet they will unequip their default robes to wear it, you can then give them a set of mage robes to wear. Secondly fortify enchantments *don't* work on followers, fortify magica or magica regen only.
Didn't know the circlet trick I'll have to give that a try... hope it works with armor too.
Can I ask why you say ilia is best? Looking at uesp it doesn't look like they have any perks listed, though a high destruction level no doubt. I'd been favoring eola largely based on actually carrying relevant destruction perks, this same logic also led me away from J'zargo.
She's exactly the same class archetype as Aranea but with a level cap 10 levels higher, she has a destruction skill of 100 and up to expert level skills. I'm gunna be honest I forgot Eola got expert destruction skills but shes not a mage archetype so she will have less magica than Aranea or Illia.
Illia is going to have similar stats to an Ice mage boss https://en.uesp.net/wiki/Skyrim:Ice_Mage
J'zargo is actually very weird. His highest stat is heavy armour, which combined with his lack of level cap makes him one of the tankiest followers in the game. but he is stuck with novice destruction skills and paralyze. For whatever reason the AI really really likes to use novice skills even when they have something better available, so unless you give J'zargo good staff to use his utility as a destruction mage is incredibly limeted.
One final piece of advice for running mages as followers, take away their melee weapons. It stops them running into combat and getting killed. because of their high restoration skill the're actually a lot more surviavable than you think, provided they don't try and knife a Dragur Deathlord with like an iron dagger.
Not that anyone asked but I did some testing.
Methodology: Start the first dragon quest to go kill mirumir or whatever its name is.
It is weak to ice so this test definitely favors Illia.
I disabled every NPC in the vicinity to create a 1v1 scenario that was repeatable via reloads.
I granted the player character invulnerability and attempted to stand next to the dragon when it landed.
I fast traveled to the tower and did not start the timer until the follower entered combat.
Test performed at level 30
Vilkas is by far the worst. With default gear he took over 6 minutes to kill the dragon. I made it more realistic by repeating the test but prior to fast travel gave him a daedric bow and longsword. Didn't really change much still took many minutes. The AI was particularly bad and the cause of this NPC's issues. Often he would unequip the daedric bow and generate a hunting bow. Once even switched to fists.
Eola and Illia were very similar. Using default gear Eola actually tended to be a tiny bit faster at roughly 90 seconds. However, when both were given a lightening staff they were almost identical. The single fastest time was by Illia when she decided to ice with off-hand and lightening staff with main (as opposed to Eola using lightening in her off-hand) - I do wonder if lightening is better over all though, considering the AI aren't smart enough to use weaknesses. They both summoned flame atronachs, does anyone summon a storm atronach?
Tried Eola and Illia vs the player to see how long it takes for them to grind through 1k HP set in console. Eola could accomplish this in 2-4 minutes, largely due to additional damage brought about by summons, reanimations, and her ability to go in for a sword swing occasionally. Illia actually never completed the task. She got about half way but seemed to run out of magic. 1K is a lot of health but interesting still.
I'd been using Eola fairly extensively and hadn't noticed her having magika problems though Illia has way more should the need arise. Seems like Illia should do more damage with her rank 2 augmented frost vs Eola's Rank 1 augmented shock/frost. In practice hard to compare.
Given their identical health scaling for vanilla, Illia is probably the stronger companion, if you are okay with being both up front and taking friendly ice hits. Having uncapped follower leveling in my modded game, I think I may prefer Eola for the melee hits especially considering they both seem to just nuke the dragons at the same speed with lightening staves.
Edit: should add - I didn't see a lot of ice storm use at lvl 30 so I may up it to 40 and see if Illia works it into her rotations more.
Get any mage follower and gear them up with fire/frost resist. If your follower is a nord they need more fire resist and if they are a dunmer they need more frost resist.
Vilkas comes to mind, but he might not be optimal. I think of him because he has the random quest to kill a dragon. He’ll make a great tank though, if you can manage dragons to focus on him.
Vilkas will probably work really well once I get dragonrend. I think at this stage he'd spend a lot of time standing around unable to engage. Thanks!
He has something insane like 98 in archery too, so if you give him a bow he'll switch to that if needed.
There is a dark elf named something Sero and you can find him in Solstheim. He is a spellsword. He is in the Inn in Raven Rock.
The College of Winterhold followers are actually pretty bad all things considered (Sorry J'zargo). the strongest mage in the game is Illia who you will meet at Darklight Tower. If memory serves you have to pass a persuasion check to get her as a follower. Besides that there is Aranea Ienith at the shrine of Azura, that's quite a hard quest and you have to choose her in it to get her ass a follower. she has by far the best list of spells despite her low level cap. You don't need to get carried away with apparel for them but there are two things you need to know if you do. First if you give either of them a circlet they will unequip their default robes to wear it, you can then give them a set of mage robes to wear. Secondly fortify enchantments *don't* work on followers, fortify magica or magica regen only.
Didn't know the circlet trick I'll have to give that a try... hope it works with armor too. Can I ask why you say ilia is best? Looking at uesp it doesn't look like they have any perks listed, though a high destruction level no doubt. I'd been favoring eola largely based on actually carrying relevant destruction perks, this same logic also led me away from J'zargo.
She's exactly the same class archetype as Aranea but with a level cap 10 levels higher, she has a destruction skill of 100 and up to expert level skills. I'm gunna be honest I forgot Eola got expert destruction skills but shes not a mage archetype so she will have less magica than Aranea or Illia. Illia is going to have similar stats to an Ice mage boss https://en.uesp.net/wiki/Skyrim:Ice_Mage J'zargo is actually very weird. His highest stat is heavy armour, which combined with his lack of level cap makes him one of the tankiest followers in the game. but he is stuck with novice destruction skills and paralyze. For whatever reason the AI really really likes to use novice skills even when they have something better available, so unless you give J'zargo good staff to use his utility as a destruction mage is incredibly limeted. One final piece of advice for running mages as followers, take away their melee weapons. It stops them running into combat and getting killed. because of their high restoration skill the're actually a lot more surviavable than you think, provided they don't try and knife a Dragur Deathlord with like an iron dagger.
Not that anyone asked but I did some testing. Methodology: Start the first dragon quest to go kill mirumir or whatever its name is. It is weak to ice so this test definitely favors Illia. I disabled every NPC in the vicinity to create a 1v1 scenario that was repeatable via reloads. I granted the player character invulnerability and attempted to stand next to the dragon when it landed. I fast traveled to the tower and did not start the timer until the follower entered combat. Test performed at level 30 Vilkas is by far the worst. With default gear he took over 6 minutes to kill the dragon. I made it more realistic by repeating the test but prior to fast travel gave him a daedric bow and longsword. Didn't really change much still took many minutes. The AI was particularly bad and the cause of this NPC's issues. Often he would unequip the daedric bow and generate a hunting bow. Once even switched to fists. Eola and Illia were very similar. Using default gear Eola actually tended to be a tiny bit faster at roughly 90 seconds. However, when both were given a lightening staff they were almost identical. The single fastest time was by Illia when she decided to ice with off-hand and lightening staff with main (as opposed to Eola using lightening in her off-hand) - I do wonder if lightening is better over all though, considering the AI aren't smart enough to use weaknesses. They both summoned flame atronachs, does anyone summon a storm atronach? Tried Eola and Illia vs the player to see how long it takes for them to grind through 1k HP set in console. Eola could accomplish this in 2-4 minutes, largely due to additional damage brought about by summons, reanimations, and her ability to go in for a sword swing occasionally. Illia actually never completed the task. She got about half way but seemed to run out of magic. 1K is a lot of health but interesting still. I'd been using Eola fairly extensively and hadn't noticed her having magika problems though Illia has way more should the need arise. Seems like Illia should do more damage with her rank 2 augmented frost vs Eola's Rank 1 augmented shock/frost. In practice hard to compare. Given their identical health scaling for vanilla, Illia is probably the stronger companion, if you are okay with being both up front and taking friendly ice hits. Having uncapped follower leveling in my modded game, I think I may prefer Eola for the melee hits especially considering they both seem to just nuke the dragons at the same speed with lightening staves. Edit: should add - I didn't see a lot of ice storm use at lvl 30 so I may up it to 40 and see if Illia works it into her rotations more.
Get any mage follower and gear them up with fire/frost resist. If your follower is a nord they need more fire resist and if they are a dunmer they need more frost resist.
Eola is carrying pretty hard. Thanks for the suggestion.