Apropos of little beyond the fact that I've been looking into the Breath of Fire JRPG series generally, have a video somebody made showcasing some of the characters' fusion forms* set to the German version of the Digimon Adventure 02 Fusion/DNADigivolution theme. (Well, that's the first half-ish of the video, it trails off into regular gameplay after that.)
It's kind of astounding to me that German dubbers chose to 1) keep the Digimon series' original soundtrack and 2) give it new German lyrics.
*In the first game, there was a specific party member who could fuse other party members into himself; this actually put a special status on the other characters and changed his stats and appearance, and I believe it let him use a few of their abilities, though it was also rather heavily a form of brute force-the fused characters didn't have very versatile combat abilities, but they did have a lot of muscle, the normal attack damage potential only outdone by the main character using a boomerang because the boomerang could hit every enemy in a battle (seriously).
The second game's fusion system actually involved fusing NPCs into the characters, causing them to transform in various ways; among the more notable transformations are of the party's dogman member into what appears to be a robot with a cannon arm, the transformation of the party's monkey-like member into what rather strongly resembles a genie, the change of the giant, vaguely rhino-like armadillo man into a tiny, cartoonish pink rhino/armadillo, and the versatile transformations of the party's gender-ambiguous/agender plant person into 1) a tiny flower bud, 2) a literalized "snapdragon," and 3) a magical girl.