Hello, I'm a Ps3 user. I've recently heard about forcing your followers to level up by using the Wabbajack, but now I've heard that there are SOME followers that the Wabbajack does NOT affect like Cicero. Can anyone please list out which followers that you can't force level with the Wabbajack?

I've found this does not work on Mjoll either!

It works on any follower that is non-essential. Some NPCs are essential until you finish particular quests. For example: Aela is essential until you find all three totems, so she can only be levelled/killed after those quests are completed. Cicero shouldn't be essential after you finish the Dark Brotherhood quests. If an NPC can be killed, then the Wabbajack exploit will work.

I though I've seen people report the Cicero is essential (probably a bug) throughout the game.

...but, yeah, what A'x said.

Thank you

Yeah I've killed Cicero once because as another member on here says a lot he's a "scumbag".

Mjoll is essential. The Wabbajack trick won't work on her.

From my experience trying to level Mjoll, if the Wabbajack is only giving you the elemental explosion effects, then the follower is essential. I literally tried to morph Mjoll into a bunny for 30 minutes before giving up and coming here for advice.

Strangely enough, I was trying to level Brelyna the other day, and only getting elemental effects on her as well. I only tried for about 5 minutes before giving up- remembering what happened with Mjoll. But, I am 99% sure that Brelyna is supposed to be non-essential, so maybe she is bugged in my game?

That happened to me. I gave up after like 10 minutes figuring she was already maxed because I'm pretty sure I was past LVL 40 when I went to Riften the first time. I found out later that she's essential and why I only got the elemental nuke effects.