Play through mission modes, you'll eventually unlock... I think it was that dude who yells "GUNDAM FIGHT" every time he sees you? Anyways, once he shows up in mission mode and you get a message from him, do missions he's an ally in (either friendship missions randomly or story missions) until he's raised to friendship level 2. Then use him as a partner until he's level 3; you can finally use him.
Pilots can't ride any Gundam that you haven't bought a license for. And you need to play with that Gundam five times before you can buy the license, which seem pretty expensive to me early on imo. And sometimes, if it's a Newtype Gundam (like Quebeley), you'll have to raise your own pilot to level 5 friendship to make them a Newtype even if you have the license. And to raise Garrod to level 5, I had to do a six star mission >__>
If he just wants to use the mech and doesn't care about the pilot, though, getting level 3 is pretty easy once you realize what side he's on. All I know is that he's not on the Those Who Pass By side (the one with Sirocco, Garrod, and Loran).
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'From now on, I'm going to call you Baron Squinty.'
KrahenProphet and Kana are on opposite ends of the Awesome Spectrum.