- Name: Guts Rock (ガッツロック)
- Number: MRR-3
- Height: 1.88m
- Weight: 1.1 t
- Hardness: 9
- Weapons: Vital Saber, Strong Cutter, Break Voice
- Transformation: Granite
- Voice: Kenichi Ono (ep 20)
- Possesses herculean strength and a heart of gold. Has a bright personality and a love of animals and nature.
- His GoBots counterpart is Granite.