You can use soul boost which boosts your character. However you need lots of souls zennies and more souls. Some of the souls are exclusive bounded to a temp event.
I hope the multiplier will be added to the free version coz of the new coop mode. It's hard now to not get detected with 1 hit kill.
hmm you could be right but we need to be sure you know .. Our specie is endangered especially now with the new coop mode which is fun but dangerous too../