Amumu - mana god
Just a build. Try it? please...

Just a build. Try it? please...

if you want mana, get rid of
and add in 
if you want mana, get rid of
and add in
Granted, Righteous gives more health regen and mana and it gives 'Eternity' and a 4 second speed boost towards enemies. It kind of overlaps with
and still have to include some beef if you want to not die instantly. Not to mention getting basically a massive speed boost after running for a while with a auto to proc a short burst of slow at max stacks, kind of beats a 75% speed bonus towards enemies that has a 90 second cooldown. Especially if the basis of the poster's build is around being more of a aggressive jumper Amumu then a tanky 'support harass amumu' which all that AP and AP bonus via mana stacking is a clear sign of a Amumu who ain't gonna be team fighting only but actually being a mean little sad mummy.~
Doesn't help that Amumu still is a close range champion no matter how you build him, so better to include more then just Armor stat item to blast anyone you want to massacre with via the power of 'hugs'.~
[slayer-pantheon-popcorn]
Read the title, MANA GOD. Therefore he needs all the mana he can get
dumb