Hydra Gem

Hydra Gems are items uncommonly dropped by Phantom Hydras. They have three different colors - red, blue, and green - each rarer or more valuable than the other, but in game, are all counted as the same item unless in crafting.

Red Gem
The red Hydra Gem is the most commonly dropped out of the three. It prevents the Player from catching on fire if there is at least 5 in their inventory/hotbar and gives them immunity to lava if there is 20 or more. Right-clicking in the air shoots the Player upward in a collum of flame and ignites everything nearby - except the player. It works mostly like an Ender Pearl, but does not damage them from use and has an offensive kick to it.

Blue Gem
The blue Hydra Gem is sometimes dropped out of the three. It provides the Player with a longer amount of time able to be spent underwater safely if there is at least 3 in their hotbar/inventory and gives them full immunity to drowning if there is 17 or more. Right-clicking it on the ground makes it work like an infinite water bucket, and if left-clicked on a mob, it shoots a small gust of water that pushes and slightly damages the mob, which is useful for pushing Zombie Pigmen off cliffs in the Nether that are bugging the player.

Green Gem
The green Hydra Gem is almost never dropped. It provides the effects of the two above, but also, no matter how many in a stack, provides them immunity to wither and poison effects. It may randomly spawn an Emerald in the Player's inventory every 2 hours, but only has a 45% chance of doing so. Villagers will offer high quality items for 1 or 2 green Hydra Gems.