Catch the Rainbow

It started with a nautilus.

If you’ve ever moved a nautilus in vanilla Minecraft, you know: it means herding it through water. One day, halfway through exactly that, it started raining — and I thought, hold on. Rain is water, isn’t it? In Terraria, goldfish get up and walk when it rains. Maybe today this thing can walk home overland.

It took damage anyway. And there I stood in the rain, watching the health bar drop, thinking the most entitled thought imaginable: how come Terraria gets rain-walking fish and Minecraft doesn’t?

This mod is my answer.

Rain = Water. That’s the whole idea. While it rains, fish in the water remember that the sky is just more water, and they come up to swim through it — cod, salmon, tropical fish, pufferfish, squids, dolphins, whatever your mods throw into the tag — never more than 10 blocks above the ground. When the rain stops, gravity remembers too. Watch an entire sky of fish fall back into the pond. The ones that land on dry ground flop around for a while, then quietly become dinner — and they drop loot, so a rainy day is a good day to fish without a rod.

It also rains fish. Some fish don’t come from any pond at all — they materialize in the air near you and just drop. Biome-aware: warm oceans rain tropical fish and pufferfish, cold oceans rain cod and salmon. The population is capped around 40.

The drowned don’t hide either. On rainy nights they spawn right out of the rain overhead — tridents and all — more that during a thunderstorm (which also lets them appear by day). Some ride zombie nautiluses into battle. But every so often, the rain sends something worse.

The Dolphin Knight. A drowned with a diamond spear, riding a dolphin, somewhere above you. It circles like a shark, then dives — with real pathfinding, it stabs with an actual vanilla spear: the faster it’s moving when it hits, the harder it hits. Then it’s gone, up and circling around for another pass. Shoot the dolphin out from under it, and it keeps coming on foot. Angrier.

Two operator commands, if you’d rather summon trouble directly: /rainow dolphin_knight <x> <y> <z> · /rainow nautilus_knight <x> <y> <z> (needs Fabric API）

Credits. Part of the inspiration: Terraria’s rain-walking goldfish and the flying fish that hunt you — and Catch the Rainbow, Blackmore’s Stand from JoJo Part 7: Steel Ball Run, for the name and the whole “walking on rain” idea.Developed in human-directed AI collaboration (GLM & DeepSeek). The icon background is AI-generated; the fish is the authentic in-game texture.