The Slug Defender is a Protogunner with a large battery on its back and electric powered hands developed and operated by Molly. It focuses in close-quarters combat. It attacks by punching the air to generate a short stream of lighting. It can defend itself from enemy attacks by producing an energy field in front of it. Charging the energy field up causes larger surge of lighting to occur and can potentially stun anyone hit by it.
There are two distinct versions of the Slug Defender:
- Blue Slug Defender: The very first and original version, piloted by Molly.
- Red Slug Defender: Its close range is still generating a short stream of lighting. However, the Slug can attack at long-range by generating piercing energy balls and launching them forwards. The energy fields now travel forward, block energy attacks, and stun enemies on contact. Once damaged or self-dissipates, the force field breaks into multiple energy balls. Its piloted again by Molly like the original version.
- Golden Slug Defender: Like the original version, it focuses in close-quarters combat and has the same attacks. But it was modified to have the electromagnetic propulsion, for improve its maneuverability and allowing it to break through enemy lines. Its polited by ordinary Regular Soldiers.