I recently rerolled a legendary that said 40% damage to stunned enemies. One of my abilities immobilizes them, but I believe that technically falls under rooting. My main question is are there specific abilities that stun enemies or does immobilizing fall into this same category?
Immobilizing counts as crowd control, but only stun counts as stun as far as I know.
Rooting is a category all of its own. Because of the quest UnderRoot Dungeon, it is player action. Basically, in order to eliminate confusion, rooting as it is normally defined does not apply.
Which is a good thing. You can apply multiples of conditions to one foe or group of foes. That stated, Stun means that they can’t attack, use skills or move; Immobilize prevents foes from moving but not attacking. Both along with 9 other conditions are considered Crowd Control. So, that means a Final Boss that is Staggered is effected by Stun, Immobilize and 9 other conditions at once.
Then would it be possible to reroll to 40% damage to rooted enemies?
If there are instances were rooted refers to your opponent, then it should be possible to get the affix to its highest point. Go to Options, go to Advanced Tooltips, click on it. Hopefully, this does two things. In know that it gives you red/green on every affix. it should give you the range as well. As long as that range is above 40, you can reroll.