User blog comment:Dennizen130/Sludge, The Disease Walker/@comment-4680018-20121127222309

That passive seems too strong, I'd say the AP scaling should be 0.2 at most. The Q and the W should have mana costs that increase with each rank, not stay flat or decrease. Also the W's mana costs should start lower, maybe around 90 and then increase to 140. The E should have lower AP ratios since it's AOE and lower mana costs at the lower ranks, maybe start at 70 and finish at 90. The ultimate's impact AP ratio should also be lowered, maybe to 0.75.

You've definitely spent time thinking about this character, just spend a little more time on the mechanics and he(/it/whatever sludge is) will be a fun champion to fight as and against.