Select arcade mode and play as a Zeon pilot. Target and destroy the G-BULL to unlock it in versus mode. Play until you reaching a space battle where you will fight the G-BULL and one other Mobile Suit. Note: This will not work if an ally makes the kill. Kill it yourself to unlock it in versus mode. Choose either the third or fourth stage, and at the second to last mission you will fight a mobile armor called BRAW-BRO. Select arcade mode and play as a Federation pilot. The only way to kill it with most Mobile Suits (or Gundams) is to jump up and hit its main body with your Beam Sword. The easiest way to encounter it is to choose the fourth stage.
Target the ADZAM and destroy it to unlock it in versus mode. Choose the first stage and wait until you get to a desert mission you should be fighting one Zaku2, one Gouf and an ADZAM mobile armor.
