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Mental Omega APYR (Almost Perfect Yuri's Revenge), often shortened as Mental Omega or MO, is a free unofficial expansion pack for Command & Conquer: Red Alert 2 - Yuri's Revenge. First released in 2005, the mod started off as a balance modification created by Speeder and Mevitar, who would later grow into the Mentalmeisters team. After a few years, the mod had grown into a de facto unofficial sequel, with version 3.3 adding a new faction - the Foehn Revolt.
Mental Omega APYR uses the Ares Expansion DLL which allows new features to be added into the gameplay by adding new units and rebalancing existing ones, making the mod almost completely different than the original Yuri's Revenge and more suitable for multiplayer gameplay, which is the mod's aim to make it perfectly balanced (hence why the mod is tagged as an "Almost Perfect Yuri's Revenge").
Mental Omega APYR features new campaigns for the Allies, Soviets, and Yuri, continuing from where Command & Conquer: Red Alert left off and branches into an alternate, expanded universe which spans over 80 missions divided into two different acts related to two stages of the game's story: the Soviet invasion to the United States and the war against Yuri. Cooperative modes for 2 players are also available.It expands upon the original game by taking on an alternative story from the events that led to Red Alert 2's plot on a campaign that spans throughout 97 campaign missions and 36 cooperative missions.
Mental Omega also incorporates numerous additions such as an entirely new faction; the Foehn Revolt, new units divided in three specific subfactions for each faction which have their own specializations, new gameplay features, new skirmish maps, new soundtrack unique to each faction, and more.
Mental Omega APYR also features the addition of hundreds of new skirmish maps and a variety of game modes, which makes both skirmish, network and multiplayer games a lot more fun to play. Multiplayer is primarily played through the CnCNet. In addition, each faction has an extensive list of unique soundtracks, composed by Frank Klepacki, Black Ice 9 and World Beyond.
Mental Omega APYR is in version 3.3.6 as of October 30, 2021.
Upcoming version
So far not much is known about the upcoming version, aside from the following:
Act Three: New Horizon that features the Foehn Revolt campaign
The addition of animated CGI cutscenes into the main story, created by the Mental Omega Animated Cutscenes Project team.
The implementation of Phobos, an Ares-compatible engine extension for Yuri's Revenge that adds new mechanics and extending current ones into the mod.
New Skirmish options: No AI Attack Powers and Auto Repairs