Higher Viktor's mana cost!!

Viktor's mana cost should be higher, especially when his new upgrading item gives him +150 mana and a nice chunk of AP for his first recall. For a champion that has everything like burst, shield and pushing abilities, and even a bit of mobility, it makes me wonder why he doesn't run out of mana. Especially since his Hex can help him sustain his mana, he can just go full burst build without spending gold on mana coverage.