The Wyrm Gun is an extremely powerful illegal gun and very effective in both Custom Robo (GameCube) as well as Custom Robo Arena (DS). It is a modified version of the Dragon Gun. In Custom Robo Arena, it has a physical appearance of a purple and red snake head. From the ground, it shoots a stream of five (four in Arena) fast purple snakehead-shaped rounds that home in on the opponent. From the air, it fires an extremely fast single round with limited homing. Quite possibly one of the best illegal weapons. In Custom Robo, this gun is used by Oboro before he has his memory erased by the Eraseur Device. It can also be seen being used by Oboro in the intro video. In Custom Robo Arena it is one of the three separate illegal guns that do not belong to a set.
This gun tends to give fast victories, so use it for time-limited battles.
Select a gun with longer range than the Wyrm. Just keep running and try to go for a System Overload.