User blog comment:LittleBigEater/God Eater 2 Rage Burst Trophies/@comment-1419424-20150702191643

That last one is obtained from breaking a part. Ketsugohōkai is the term for unbounding a part, which kind of goes to figure with the English name translation you have there.

"A Brief Rest" I believe is obtained from viewing the scenes that come from selecting one character's support skills post-battle enough times.

Saying "just use your weapon" for the attribute attack is inaccurate. You actually need to hit an Aragami's elemental weakness with a weapon of the appropriate element.