The grey test version is given to you during a mission chain, when you are given a mission to get the Three Red Crystals in the Zephyr Power Plant . It has fantastic attack on Zephyr Enemies and basic on everything else.
The updated version is given after completing the mission to get the Three Red Crystals. It has valiant attack on Zephyr Enemies and fantastic on everything else. It also has the Invapad ability, which makes the user invulnerable to enemies and does 4 damage to enemies around you.
The green version is the same as the yellow except it is GM only and it has one hit smash, it has better stats than the others as well.