User blog comment:Linathan/Unit Spotlight: Emerald Radiance Libera/@comment-27007929-20150922010550/@comment-26140304-20150922021921

As noted above, I would choose Anima over Guardian for the extra HP. Now, in terms of your Arena Squad, you'll want to use Quaid for the 100% Atk boost if you're using a rainbow team. If you don't have a rainbow team, I would use Libera.