You guys reverted his Q and W but kept the mana cost on his W (his W used to cost 0 mana.) So essentially the Kog we have now is just a nerfed season 5 Kog since his ult is much weaker and his W now has a mana cost.
Not trying to complain about this I just want to understand the reasoning. Kog wasn't OP at the end of season 5 or anything.
Devotìon1 votesOld Kog'Maw had a mana cost on his w in the past. they may have removed it in the past, but I don't remember when they did that exactly.
Randomonium1 votesKog'Maw had a mana cost until patch 4.4 when they removed it. When they reworked him for the season 6 pre-season update they gave the mana cost back. Why revert the power of his W but keep the mana costs?
Rebonack1 votesOld Kog'Maw had a mana cost on his w in the past. they may have removed it in the past, but I don't remember when they did that exactly.
IIRC, they removed it because they wanted Kog's main power source to be gated around cooldowns only since the rest of his kit was already heavily mana-gated.
Dracocrash1 votesRiot: were too lazy to balance 5.0 as kog so we will revert him! "But to keep our ego in check we will not revert his W animation, his W mana cost, and his ult! OK BYE!"