Thou Shalt Not Kill Radroaches

[Velocity Boy]

Assassin's Creed? Would poisons count here? How about hiring Mercenaries? Using assassins? Assassin's Creed should be a stealth game, so why not?

I don't think it's possible in Assassin's Creed (even Revelations, where you have the assassins early). There are numerous missions where you don't have access to your guild or mercs, but still have to kill at least one person. You have a huge variety of ways you can kill your target. Poisons only would be an interesting challenge though