|Fanmade artwork of Bass using Treble Boost by JusteDesserts.|
Treble Boost is a utility weapon exclusive to Bass that allows him to fly freely and shoot three shots at once in a spread shot when he fuses with his robotic companion Treble. It first appeared in Mega Man 8. This version was later made usable by the player in Mega Man & Bass, Mega Man & Bass: Challenger from the Future, and Mega Man 10. In Mega Man Maker, it replaces the Rush Coil/Proto Coil, Rush Jet/Proto Jet, Power Adaptor, Jet Adaptor, and Super Adaptor.
To activate it, the player must press fire and walk into Treble while he appears. When summoned, Treble will be growling for a while before disappearing if Bass does not fuse with him, similar to Rush's behavior when he is summoned for his Coil and Jet utilities. The combination remains until Bass changes to another weapon or the energy runs out. When the weapon loses all energy, Bass goes to his normal stance.
During the Treble Boost, the shots are distinct from Bass' normal buster shots. They can pass through walls and they do 1 point of damage, but with the drawbacks of not being able to fire rapidly and needing to wait the three shots to despawn before shooting again. Outside of the fusion, Bass will fire shots with the same characteristics of Mega Man's uncharged Mega Buster shots.
The concept of stronger shots and its base mechanics come from Mega Man & Bass, while the fusion with Treble was taken from Mega Man 10.
When destroying Weapon Blocks, they can only be destroyed by a specific version of the Treble Boost. This has to do with its substitute for the utilities of other characters, who need the determined utility weapon to destroy the Block. The Rush Coil and Jet still have their own ID.
- When first introduced, there was a bug that occurred where if Bass picked up a Weapon Capsule while transformed and did not touch the ground when picking it up, he would appear to turn back to normal with the weapon equipped but would maintain his flying ability and inability to be staggered, allowing him to fly indefinitely with the new weapon equip. It was later patched in a following update.
- A similar glitch to the previous was later discovered in versions of Mega Man Maker after the original was removed. By spawning Treble with the Treble boost or a version of the Rush Coil/Proto Coil in a specific spot on one room and then quickly going into another, the player character can use Character Capsules and either Weapon Capsules or Weapon Removers to force the player to become Bass and then either remove their Treble Boost weapon or give them their set primary weapon. This will force them into their primary weapon without them pausing or quick-switching. If they then return to the previous room Treble or the Rush/Proto Coil will still be there, allowing for Bass to then fuse with them upon contact despite having a different weapon equipped, giving him all his Treble Boost abilities but maintaining the shot-type of his equipped weapon. This glitch was made impossible to do as of the 1.6.0 update as spawned in Treble, Rush, and the Proto utilities will now despawn if the room they are placed in exited.
- If Treble is summoned and lands just as a Yoku Block appears one block of space above him, he might not complete his teleport animation and will be stuck in the last frame, causing him to look like a massive purple and white blob. He can however still be merged with like normal if walked into. He does not however seem to teleport away if left alone for a while as the game may still think he is trying to teleport in.