[Cubical]

maybe a better idea would be to create a 'Parkinson disease' that will spread through era that causes you to walk really slow and cause you to twitch and change directions/fire your weapon randomly. The only cure would be a cash shop antidote that cost $10 usd that would last for 5 minutes but for ever parki patient you kill it extends it another 5 minutes.

The antidote should have diminishing returns as well so each time you drink it it becomes less effective.