The Aqua Blaster is available from the start of the game, used to put out the fire in the Flutter. It has a rather interesting design to say the least, probably meant to resemble a futuristic fire extinguisher. It has a couple of uses that are well-known, such as putting the fire out in the Flutter, extinguishing Johnny’s turrets on Nino Island (although Johnny has his own extinguisher on hand), and for dousing the Parabola if it takes too much damage. Granted, the Parabola incidence can be avoided altogether with a good buster setup, but it’s not a bad idea to have an extinguisher on hand in case things get hairy. The Aqua Blaster also has the lesser-known ability to be able to douse certain reaverbots as well, such as the Fire Frongel.
Capcom really could’ve had this thing do a lot more than that. I’ve heard people say that you can use it to “cool yourself off” after being burned, but I’ve already proven that false. Roll could’ve at least upgraded it to fire hose status, similar to Mario’s FLUDD technique in Brawl (or Squirtle’s Water Gun); that is, a non-damaging attack that stuns enemies. Its energy is infinite, although the recharge time can be a little annoying (particularly in the first mission), and it doesn’t help that Roll charges you more cash the longer you take on the mission.
The Aqua Blaster is less of a special weapon and more of a utility, and its uses are rather minimal, but it does do as advertised and then some. I’m giving this one a 7/10.