Silencer is an online, multiplayer-only video game by Mind Control Software that was published by the World Opponent Network (WON.net) for free play on their website in January 2000.

[5] It saw a number of beta updates before it was removed, without explanation, from WON.net's website in September 2000 and the multiplayer servers shut down in October 2000.

[6][7] Silencer is a bit of an anomaly in that it managed to spawn a fan-made WONswap site,[8] 7 known fansites,[9][10][11][12][13] plus a legacy of independent multiplayer servers and game clones (see below), from its short run as an open beta on WON.net.

The game involves five competing agencies that send agents, called "Silencers," into the field to hack public computer terminals with the goal of exposing the Martian government's secrets.

[8] The five agencies each have specializations which give them various advantages over each other (including access to one agency-specific item): At the start of each game, each team's leader creates a hidden door to a base at any location on the map they choose.

As the game progresses and intel is collected, teams will learn the location of a terminal with a top secret.

Disguise is an important feature of the gameplay as it allows a Silencer to appear as an NPC to pass unnoticed by guards, robots and defense lasers.

"[14] Silencer was announced as early as April 1996 by SSI, the publisher of Mind Control's first title, Alien Logic: A Skyrealms of Jorune Adventure.

[17] Silencer was released as on open beta on WON.net at version 0104:[6] Mind Control Software announced their closure on May 26, 2000.

[7] (Mind Control Software re-opened its doors years later in 2005, and closed again in 2013 as Electrified Games.

[25] In February 2007, Mind Control admitted publicly that they were discussing making Silencer open source.

[37][38] Another clone of Silencer, dubbed zSILENCER, was released in 2013, along with an online multiplayer server, plus website.

[39] While the main website is still online, the wiki is gone, account creation and the forum are dead, and the multiplayer server was last seen in October 2020 (as of April 2023).