SAS Zombie Assault Wiki

Events are a feature in SAS: Zombie Assault 4, similar to the Daily Missions from the mobile port of SAS: Zombie Assault 3. Their inclusion in SAS 4 was announced on a Ninja Kiwi blog on September 5th, 2014[1], and their inclusion in the mobile version was announced on May 1st, 2015.[2]

They can either be passive events, like Spitter Bounty, which tracks how many Spitters the player kills in Multiplayer matches, or matches themselves, like Alpha Virus. The more a player completes the requirements for an Event, the higher their rank gets on the leaderboard. There is a "Bounty" event for each type of zombie, along with four other events that require direct participation.

Once the Event is up, the player will be rewarded based on their placement on the leaderboard (if they at least reached the Bronze Rank). Being in the top 100% will give a green question mark, 75% a Bronze Rank, 50% a Silver Rank, 25% a Gold Rank, 10% a Platinum Rank, and finally 1% a Diamond Rank.


Alpha Virus

Alpha Virus Event.png

Alpha Virus is a Multiplayer Match the player has to directly participate in (meaning it is different from the regular Multiplayer Quick Match). Deaths aren't recorded in this gametype. It is unlocked at level 15. All of the maps are altered, reducing them in size by prohibiting the players from venturing beyond a certain area. Additionally, sections of walls on some of the maps are destroyed, allowing the players more room to navigate in the confined area. Further, there are holes in the walls of some maps, serving as spawn points for zombies.

The Alpha Virus, the focus of this event, is 'contracted' either by finding it when the Match starts, or by picking it up when another player dies and thus drops it. The player with the Alpha Virus will have a blue aura, and is designated with a blue skull-and-cross bones on the minimap. Once a player has it, they will move slower and their health will degenerate; additionally, all of the zombies will flock to them. The zombies will only attack players that don't have the Alpha Virus if they are between them and the player with it. Players revive much faster when knocked out, and the match won't end if all players are down at the same time. As the player holds onto the Virus, their score increases, by increments of 5. If/when they do die, an explosion goes off around them, one-hit killing every zombie and allowing other players to move in quickly and get the Virus. The virus will explode on its own after a certain amount of time holding it. The Match is ended only when one player reaches 800 points, who is then the winner.

If the player does not have the Alpha Virus, it is best to stand out of the way of the zombies and not shoot them. This way, the other player with the Alpha Virus will die as soon as possible (allowing the player to snatch it up).

Note: NK has confirmed that this event mode was replaced with virus samples.

An Alpha Virus Match—note the score listing on the left.

Zombie Bounty

A Zombie Bounty before the "re-imagining"

Zombie Bounties are passive Events, meaning the player is automatically participating in them (unless if they don't play for the whole time period of the Bounty) whenever they play Multiplayer (Quick Match, Private Match, Active Events, and Nightmare too). The focus is to kill whatever type of zombie is specified in regular Multiplayer Quick Matches. The player must kill the specified zombie by themselves or the kill won't count. Fast-firing weapons are recommended to get as many zombies as possible. Zombie Bounty's rewards are slightly less than the ones of active events.

In the July 21st, 2015 update, Bounties were "re-imagined" (along with the addition of the Virus Samples event). The zombie a specific Bounty focused on now receives buffs (such as Spitters becoming super-fast).

New Bounties

Last Man Standing

Last Man Standing was included in a patch on September 24th, 2014, according to the patch notes on the main menu. The goal of this event is to stay alive the longest. Like Alpha Virus, it is a Multiplayer Match separate from the regular Quick Matches (meaning the player has to participate in it directly.) When a player dies, they will not respawn, and can choose to either stay as a spectator or finish playing that match. Like in Alpha Virus, some maps have some areas restricted, some maps have sections of walls destroyed, and zombies will additionally spawn from new locations.

If there is only one player present (i.e. when all players leave that player behind), the game will end two seconds after it begins, and no points will be awarded, counting the player to be in 'last place.' Furthermore, the player who comes in first does not get 5 points, but rather, gets points equal to his place from the bottom, that is, the last person gets 0, the second to last person gets 1, the third to last, 3, and the fourth to last, 5.

Virus Samples

Virus samples was added in the July 21st, 2015 update (along with improved Zombie Bounties). This event is a form of indirect PVP where the players try to collect as many vials of Virus Samples from dead zombies as possible. The person with the most vials get first place. Unlike in Apocalypse, in this event you revive with full health a little faster than normal. The more vials you get, the higher your score will be. Bloaters drop larger vials than normal, and bosses drop huge vials. Each normal vial = 5 points, each Bloater vial = 50 points and each boss vial = 100 points. You can get strongboxes in the event. Picking up larger vials will give you cash. There is also a Halloween version of this event, called Candy Samples, Easter version, called Egg Hunt and Christmas version, called Present Samples.


Apocalypse was first released on October 29th, 2014. The aim is to survive as many waves as possible until all players are down at the same time. Like LMS and Alpha Virus, some areas are no longer accessible, and some new paths have been built to prevent players from getting surrounded. The game is played in rounds, with certain rounds spawning bosses. If players fail to kill all zombies from a certain wave, such as in the case of a boss, the next wave will start within a set timer.

Project Zombie Massacre

The aim of PZM is to kill as many non-boss zombies as possible before they take over "the planet". There will be an amount needed to be killed, displayed on the event button. Everyone who participates gets the same reward.

Contract Bounty Do multiplayer contracts. Annoying now since... well the game is kinda dead :( so this event is harder because doing contracts solo doesn't affect your score.

Contract bounty.png

Project Zombie Massacre Events screen. (From May 6th, 2016)

Project Zombie Massacre updated rewards screen. (From May 3rd, 2016)

Apocalypse/Last Man Standing zombie buffs

After the June 30th, 2015 update, apocalypse and last man standing zombies were massively buffed. Every wave, zombies will get 5% faster, 15% more health and damage, and ignore 1% more armor. Because of this, after wave 20, almost all bosses will be a 1-hit kill. The same thing happens in last man standing, except at a much faster pace.


There are five different types of rewards:

  • Turret
  • Nightmare Tickets
  • Alloy
  • SAS Cash Only
  • Boost

All of the reward types (except SAS Cash Only) give strongboxes and SAS Creds as a reward, the amount depending on what other rewards are available. The SAS Cash Only gives a small prize of a few Creds, and not only does not give any rewards other than cash, it also gives less cash then any other reward. The Turret event provides turrets, the Nightmare Ticket Event provides NM Tickets, the Alloy event provides Alloy, and the Boost provides a certain amount of time for free boost for every mission. Sometimes, diamond will give you 2 black strongboxes, 2 nantonium strongboxes, 5 promethium strongboxes, and 20 SAS Cred Packs.

The turret rewards.

Boost Rewards

Diamond Medal Transparent.png
Diamond: Top 1%:

4 Nantonium Boxes, 5 Promethium Boxes and 20 SAS Cred Packs

Platinum Medal Transparent.png
Platinum: Top 10%:

3 Nantonium Boxes, 4 Promethium Boxes and 12 SAS Cred Packs

Gold Medal Transparent.png
Gold: Top 25%:

3 Thulium Boxes, 4 Molybdenum Boxes and 9 SAS Cred Packs

Silver Medal Transparent.png
Silver: Top 50%:

Promethium Box, 2 Molybdenum Boxes and 5 SAS Cred Packs

Bronze Medal Transparent.png
Bronze: Top 75%:

Neodymium Box, 2 HMG Turrets and 3 SAS Cred Packs

Super Events

Main article: Championships

Super Events were a type of Event that could be found mentioned in the SAS 4 SWF file, and later turned out to be Championships.

Skill Focus

  • Kills using a certain skill

Boss Kills

  • Kill a certain amount of bosses to get a reward based on your leaderboard ranking.


  • An event glitch that happened in 2015 while developing the Super Events.

Storm of Bullets

  • Earn medals in bounties and Virus Samples events and by killing bosses in all game types.

Elite Squads

  • Earn Super Event Medals by killing bosses in Apocalypse events!

Lone Wolf

  • Earn medals in LMS and Virus Sample events!

SAS Blitz

  • Earn medals in all events and by killing bosses in all game types.


  • Due to the [BLACK] Version weapons and gear update, you get a chance (in Events) to get Black Keys from your reward when the Event is over. Diamond = 10%, Platinum = 4% and Gold = 0.5%
  • The last 25% of people in events are given a green question mark as their symbol, it is unclear whether NK didn't have another idea for a medal for them or if NK just decided they deserve it for not playing MP.
  • The differences between the medals are almost invisible besides the colors and meanings. With Bronze to Silver having no differences besides color, Silver to Gold having no differences besides a thin metal outer layer and different colors, Gold to Platinum having no differences besides making the thin metal outer layer connected to the main medal and thicker and different colors, and the Platinum to Diamond having no differences besides some extra points and different colors.