Each difficulty has different zombie spawn rates and rewards. [Plz add to this, not accurate so you're welcome to edit]
Reward:100$ - 175$
Start Infects:2 - 4
Reward:200$ - 275$
Infected Chance: 30%
Start Infects: 4 - 6
Reward:300$ - 375$
Infected Chance: 40%
Start Infects: 6 - 8
Reward:400$ - 500$
Infected Chance: 50%
Start Infects: 8 -10
Special Cases Edit
Infected Chance: 60%
Reward:470$ - 500$
SBF, FFA, and MMA:Unknown (Always)
This gamemode was exclusive to the Halloween Obby map, which was in the Halloween 2014 event. In this gamemode, players will have to complete an obstacle course to achieve a key to vote for lord pumkin, or a pumpkin bomb.
This gamemode is exclusive to the OpenFields Map, which is in the Easter 2015 event. In this gamemode, players and win 1st, 2nd, or 3rd place in a bunny race. Reward depends on place. You will also get some cash.
1st place: 3 bunny points
2nd place: 2 bunny points
3rd place: 1 bunny point
The smaller the server, the more likely you will become an infected.
The harder the difficulty, the more likely players will spawn as special infected.
Place hasn't decreased the spawn rate of smokers ever since the Winter Games so spawning as a smoker is likely.
Crawlers spawnrate is 50% in layby no matter what difficulty it is.
Your percentage on being a zombie lowers down during every round when you spawn as a starter zombie, but increases the more you spawn as a survivor.