I believe he is a bad tank (he can, but like he's not good at it)
not that great as support and bad damage in general (unless ap)
If he jungles, his ganks it isn't that great of a gank and has no damage while ganking
only 1 damage ability (expect for ultimate, which can be canceled)
i think riot should think about reworking nunu :) 
daft inquisitor3 votesI think Nunu is fine the way he is right now. I love the big fellah.
EleventhCarry3 votesYes please he has some great abilities for a team cc comp but he lacks usefulness in lane other than heres some attack speed or oooooh let me stand in the way.
eGmaximum2 votesNo. Absolutely no. Nunu already has 1:1 Ap scaling on his snowball. Not to mention that his ult is greater than 1:1 scaling. The fact that you can cancel his ult makes it so nunu is a situational pick that can fit extremely well into the right team composition and not an overwhelming monster of a champion that can quite literally snow ball out of control in every game.
daft inquisitor3 votesIt's more about kit than damage numbers. You can have numbers buffed/nerfed without a rework. The topic is about his kit rework, you scrub.
Earl Eulrich2 votesI would like them to add some dps to his autoattacks...maybe have his e debuff the target so it takes bonusdmg from nunus autohits or sth. - right now he really would need some more sustained power, because he just does not scale if he cannot get a perfect ultimate later on in the game - which only happens in 1/100clashes.
Bastilean1 votesI don't have trouble playing him support. Honestly, I think he's a strong pick with the right adc champions like Sivir.
Tulare1 votesThis is roughly how I view Nunu. Even playing him as jungler, I don't really aim to be "the tank" nor do I worry excessively about ganking. He's amazing at messing with the enemy jungler, provides decent utility, and decent tanking. If your support is one of the more aggressive options then having Nunu as jungler gives the team a second source of utility during fights.
For example, maybe he can't secure a gank when he ambles into top lane but if he can help drive off the enemy laner and then Blood Boil the friendly laner, they can make a significant dent in the turret before Nunu moves on.
During teamfights, you don't need a perfect ulti to contribute. Keep your marksman boiled, tank a little damage, keep somebody from getting away, and then capitalize afterward by getting the dragon and the enemy's jungle buff.
TLDR: Nunu isn't designed to be a solo act but he's excellent, as jungle or support, at helping a team secure objectives.
BlackChina1 votesit would be nice if Nunus blood boil would also do AoE damage to enemies nearby him and his target. This would makes his ganks a little better or at least be of use when he goes to a lane. Also his q would be better if he could "regurgitate" what he ate to cause damage at the price of not healing as much (like Syndra's force of will)
