If you attack with it, more card advantage
While this doesnt sound like much, the Pokemon in this game dont have much Retreat Cost to begin with, so reducing it by one is just as good as being able to swap out for free
Each song card states that a character with the right ink cost (or the special Singer ability) can sing the card by exerting that character
These are pretty similar sizes, the coloring is fairly similar, I'd say maybe the coloring is a little bit better on this one on the right
Furthermore, if their trainer knows that their Beheeyem BREAK is about to get knocked out, they can send all the energy attached to them to benched pokemon to prepare for upcoming tactics while also slamming the foe with 100 damage
The third Monstrous Compendium will be free for all on D&D Beyond and is already released