Zombie Mode is the first PVE (Players vs. Enemies) based mode CrossFire, requiring players to cooperative to finish the map's preset goal. In most case, the map contains NPC-controlled Zombies confronting players and they must be killed / dodged in order to process on.
Originally, this mode was known as Challenge Mode. Since the arrival of several new modes, it has been broken into several sub-mode as follow:
- Main article: Challenge Mode
The original ZM variant, requiring players to defeat hordes of zombies each round and then kill the boss at final round to win. It has four types, including two basic types and two upgraded types:
- Survival: Players start with only melee weapon and must pick up weapons to defeat zombies along the way. The map will progress from one point to another until the final wave.
- Assault: Players start with their equipment and fight off zombies in an enclosed area.
- Assault Advanced: Upgraded from the classic Assault Mode with BP earned in match by shooting zombies that can be spent on Item Shop for support tools. Only available in Crater 2.
- Boss War: Focus on boss battles, similar to Boss Arena's concept. Players can choose an active skill (F) to be used against zombies and bosses along with the default Slide skill (Shift).
- Main article: Racing Mode
A lesser-known ZM variant and more competitive rather than cooperative, players will race against each other in an off-road track using Hoverboards, and they can score points by shooting targets or killing zombies along the way. This mode shares the reward system with Challenge Mode but score earned during the race won't be used to exchange for safes - instead, it's used as starting scores when playing other ZM maps.
This mode is considered completed, as currently there's only one map for this mode.
- Main article: Defense Mode
Known as ZM 2, this is a more passive style challenge that requires players to protect a designated object against incoming hordes of zombies. Players can buy tools to help defending the place with the in-match credit system (Earned by killing zombies).
This mode is considered completed as Trial Challenge has taken its place following Hell Tower's release.
Trial Challenge Mode
- Main article: Trial Challenge Mode
AKA ZM 3, this mode goes back to the classic Assault Style in Challenge Mode which tasks soldiers with clearing out an infested area and kill its guardian boss to win. However, soldiers can deploy tools to help fighting zombies (Varied based on their chosen class), and death is not permanent after losing all default lives. Instead of the traditional 3 difficulties, there are now 5 to choose from, with the latter three introducing re-fights that require soldiers to kill the bosses one more time to win.
This mode is considered completed as now it has been back to the original Challenge Mode following Crater 2's release.
In some versions, players only have 8 basic lives which recharge per day. A maximum of 2 is used in each match. After all lives are used up, players will start with 0 life.