A weapon called "Fluid cannon", you can fill it with any fluid just like buckets or cells or capsules, it can hold up to 16 buckets, and on rightklick it shoots the stuff out with a particle that has the fluid's texture. When it hits a block, nothing happens, when it hits something living, it does something depending on the fluid you are shooting, e.g. lava will maybe deal 4 hearts of damage. Some other fluids should apply certain portion effects /Liquid Ender teleports you randomly. Because this had to be coded for every fluid in the dictionary, you could make it like "If nothing special for this fluid is coded, just make it deal 2 hearts of damage"
Please tell me your opinions about it.

Closing this issue for now.