Malzahar channels the essence of the Void to suppress an enemy champion over a zone of damaging negative energy.
Malzahar suppresses a target champion for 2.5 seconds, dealing 125/200/275 (+80% Ability Power) magic damage over the duration. A zone of negative energy is created around his target for 5 seconds, dealing 2/3/4% (+[1% Ability Power]%) of nearby enemies max health as magic damage per second.
Yes, it can be removed with QSS, but that requires everyone on the team to spend 1300g. 1300x5=6500g. So either you lose a member of the team every 48 seconds late game, or you put your team at a 6500 gold deficit.
It needs to either be a skillshot, have a longer cooldown at max rank, or not deal %HP damage. Something. This ability is an idiot-proof point-and-click delete button.