Decibel

"HA, SORRY! IS IT OKAY IF I COME WITH YOU? I'M NOT MUCH GOOD IN A FIGHT BUT I CAN DO OTHER STUFF! I HAVE SONIC POWERS STRONG ENOUGH TO MOVE HEAVY OBJECTS - EVEN DESTROY THINGS SOMETIMES!"

- Decibel

Decibel is a Spark that appears in Mario + Rabbids Sparks of Hope, located in Pristine Peaks. Decibel is found in a tree not long after the heroes land in Pristine Peaks. Unlike other Sparks, Decibel does not fight in battle. Instead, Decibel flies into Beep-0, granting him the Wave Power, enabling Beep-O to move certain blocks, rocks, and destroy weaker rocks.

Decibel is a glowing purple Spark that is highly excited, as indicated by its text boxes containing all capital letters. It even destroys a rock when the heroes free Decibel from the tree.