Sephiroth exists in The First Soldier timeline, as his experiences during this era will be covered in the Ever Crisis, but the playable version will be his adult iteration from FF7.
The First Soldier is an FF7 battle royale title for mobile devices, where teams battle it out using firearms and Materia, as well as fighting monsters that spawn on the map. The story of The First Soldier (what little there is) acts as a prequel to FF7, as it shows the formation of the SOLDIER unit. The First Soldier is a free-to-play game that lets the player create their own character, with the paid elements centered around loot boxes and character cosmetics. The cosmetics are one of the most interesting aspects of the game, since some do things like bringing FF7's retro sprites into The First Soldier.
The latest update for The First Soldier is bringing another famous face from the franchise into the game, or rather, it's allowing players to turn into him. A video on the official Square Enix YouTube channel has announced that the Variant Mode is now available in The First Soldier, and it will be part of the game until August 31, 2022. In Variant Mode, players have the ability to turn into Sephiroth and use his powers against other players.
Final Fantasy VII The First Soldier's Variant Mode Lets Players Turn Into Sephiroth
In Variant Mode, a team of three variant players must battle against nine regular players. It's the goal of the regular players to destroy two locations on the map, while the variant players must guard them. The variant players have the ability to transform into some of Final Fantasy's most iconic monsters, including a Bomb, a Cactuar, and Bahamut. There is also a Slug-Ray enemy from FF7 that players can turn into as part of the Variant Mode. These transformations provide massive strength boosts, making them an equal match to the larger team they're facing. Players can also turn into Sephiroth and unleash his attacks against the enemy, including slicing foes with the Masamune, performing his Hell's Gate downward stab, or summoning meteors to batter enemies over a wide area.
This isn't the first time that The First Soldier has added content like this as part of timed modes, as the second season of The First Soldier added a Crisis Core boss for players to fight. There are still plenty of FF7 characters and enemies to go, so The First Soldier could see many more updates like this in the future. Fans might one day see the other of SOLDIER from Crisis Core become playable, or face the Weapon monsters in a future The First Soldier update.
Source: Square Enix/YouTube