Below you will find a categoric list of all challenges and what my intentions were. With that said, everyone can play these challenges however they want, those below are my versions.
Drop Weapon after a kill: Every time you knock or kill someone you have to drop the weapon you killed him with. You can't use the same weapon twice in a row. For example : you knock someone with a blue AR, you have to drop it, after that you can pick every AR exept for the blue one, however after you knock someone with a green AR for example you can pick a blue AR again.
Jump at the end of the bus & Jump at the beginning of the bus: No-Brainer jump either as soon as the jump-timer is down or get kicked out by the bus driver.
Emote after kill: After you knock kill someone you have to emote, it doesn't have to be long, but the emote has to start.
Reload after every shot: As it is written you have to reload after every single shot, i recommend a shotgun or a sniper for this curse.
Only heal completely: After you've taken damage and want to heal youself, you have to heal fully.
Shakedown every enemy: As soon as you knocked someone you have to shake him down.
Don't move for 5 sec after kill: After you knock or kill someone you have to stand still for five seconds, you can look around and shoot but you can't use the movement or crouch key.
Only one weapon for the game: With this curse you can only have a single weapon in you inventory at a time, you can however switch it with a better weapon, or pick a completly different one.
First weapon only: As soon as you touch the ground the curse begins. The first weapon you see you stick with. That's your only weapon for the game, you can't drop it, but you can use an upgrade item such as an upgrade bench, screws and bolts, bones, gear parts etc.. If you get revived at a revive bus the old gun is gone and you have to pick the first one you see.
In other than solo : Everyone drops at a diffeent named location: Reroll the locations for each teammate and let them know where they have to drop.