Skeleton drowned

Opal is made from bone underwater after long periods of time. A new mob called an Opal Hunter (working on it). Their attacks will cause debuffs, they should have a low spawn rate. They would come in 5 varieties, red (Hunger and nausea), white (Weakness and blindness), black (poison and slowness), blue (Weakness and slowness), and spectral (withering and levitation).  Maybe have them only spawn when a player attacks a dolphin or an axolotl. They should attack with a cursed mangrove bow, if dropped would have low durability, HIGH attack, and require potion tipped arrows to work, would cause debuff splinter with 15% chance, causes no tools to be used in duration of 3 seconds. non-craftable? maybe random chance to spawn on magma blocks underwater. Opal hunter has lowish health in exchange. I have no claim to this idea btw, its all yours.