Although Gazzer is a useful slug, it does not have much firepower, its moveset heavily geared towards non-toxic laughing gas. Bludgeon is Kord's favourite slug and he uses it more often. So, although Gazzer is a useful slug, it does not have much firepower, making it mostly useless in battles.
Gazzer slugs are more into offensive tactics, similar to a Flatulorhinkus. Gazzer slugs can weaken a group of opponents by forcing them to laugh uncontrollably due to laughing gas. Kord, even though he's a prankster, does not mean he is poor in decision-making. He prefers to use Bludgeon, his Rammstone. He also likes using Hop Rock and Grenuke slugs. These three slugs are more attack based.