Wyrmius is a hidden side-scrolling Shoot 'em up minigame where players control a Wyrm Sentinel to defeat Corpus enemies. Players can access Wyrmius by typing in Wyrmius as the email address in the login screen and leaving the password blank, or by equipping the Wyrm or Wyrm Prime Sentinel and selecting the "W" loadout under Appearance. The highscore of this minigame can be seen in the leaderboard by entering player's Profile tab.
This minigame sees the player take control of a Wyrm Sentinel on a horizontal 2D plane that constantly scrolls to the right in a Corpus Ship. and moves the Wyrm up and down respectively, while and control left and right movement. Alternatively, the arrow keys can be used for movement. The Wyrm's weapon is fired using or , and is an automatic weapon that can be fired at full auto by holding down the fire key. The goal of the minigame is to traverse throughout the level to defeat enemies and ultimately the boss of the level.
Although initially armed with a Laser Rifle, enemies may drop a Mod upon death, which will change the Wyrm's main weapon depending on its color. Picking up mods of the same color will also upgrade your weapon:
- Red mods will make the Wyrm fire Ogris rockets in an arc. Stacking red mods will add an additional arcing rocket.
- Yellow mods will make the Wyrm fire Lanka projectiles that penetrate multiple targets. Stacking yellow mods will add additional projectiles that are parallel to each other.
- Blue mods resets the Wyrm's weapon to the default Laser Rifle. Stacking blue mods will cause it to fire multiple projectiles in a wide spread.
The mod will cycle colors while not picked up, allowing players to choose which weapon they want to get if they're planning on upgrading their weapons. Losing a life will not reset the weapon type used, however it will downgrade the weapon.
The player has a stock of three lives represented by a Wyrm icon, and each life is consumed if the player is hit by enemy fire, which will destroy the Wyrm. Losing all three lives results in a game over, and players are given the choice to try again from the beginning or quit.
- Wyrmius was first revealed in the TennoLive 2014 event, and was formally added into the game in Update 15.11.
- The name is a portmanteau of Wyrm and Gradius, the latter of which is a long-running series of scrolling shooters developed by Konami.
- The Corpus ship is being taken over by Infested tendrils, shown at the beginning breaching the ship itself and outside in space.
- It is possible for the entire screen to go black resulting in the game freezing if one holds down S at the beginning of the game for a long time.