Tropics is a hot, wet, rainy overworld biome. Two mods add a biome with this name: Biomes O' Plenty adds the first, and Regions Unexplored adds the second, which has different terrain, trees and ground cover. Both are lush, humid biomes with palm-like and jungle-style vegetation and a mix of passive and hostile mobs. Neither is on the pack's list of biomes weighted 6× for horror, but Born in Chaos mobs and structures still appear in both, so the biomes are not safe after dark.
The Biomes O' Plenty Tropics has a temperature of 0.95 and a downfall of 1.0, and it rains. Its water is tinted #43D5EE, its fog #B2EDFF and its sky #66BCFF, which gives the biome a bright, saturated look. Its terrain includes disks of white sand and white sandstone near the surface. Trees and flowers come from the mod's own tropics features, and the ground is covered with short bamboo, grass, blue hydrangea, rose bushes, sugar cane and melon patches. Wild rice grows in the water. Lakes of lava form both underground and at the surface.
Regions Unexplored Tropics
The Regions Unexplored Tropics has a temperature of 1.05 and a downfall of 0.95, and it also rains. Its fog is #C0D8FF and its sky #6EB1FF. The mod gives it its own grass and foliage tints, and its trees are palms, jungle trees and oak bushes with flowers. Below Y=65, the surface is sand in noise-selected patches, and sandstone forms on the ceilings in the same patches. Ground cover includes elephant ear and hibiscus patches, along with palm and jungle shrubs.
Generation
The Biomes O' Plenty Tropics covers about 0.01% of land and the Regions Unexplored Tropics about 0.04%, so both are rare compared with most overworld biomes. Both are tagged as rare biomes.
The Regions Unexplored Tropics also replaces part of vanilla Mushroom Fields at a weight of 20, alongside Alpha Grove and Ashen Woodland. In a mushroom field area, a player may find it instead of the vanilla biome.
Fear Nightfall does not weight either biome for horror. The pack's horror weighting (6×) covers biomes such as dark forest, Bayou and deep dark, but not Tropics. Horror structures from Born in Chaos are still placed in both biomes, and the pack places horror structures about 30% closer together than vanilla spacing.
Features
Trees and plants (Biomes O' Plenty): the mod's tropics tree and flower features, plus short bamboo, grass patches, blue hydrangea, rose bushes, sugar cane, melon patches and wild rice.
Trees and plants (Regions Unexplored): palm trees, palm shrubs, jungle trees, big jungle trees and oak bushes with flowers. The tree selector weights palm trees at 2 and oak bushes with flowers at 3. Shrubs are jungle and palm shrubs, and patches are elephant ear and hibiscus.
Terrain: white sand and white sandstone disks (Biomes O' Plenty), and sand and sandstone below Y=65 (Regions Unexplored).
Ores: both biomes use the standard overworld ore set. Born in Chaos adds infected diamond ore and Black Argillite placements, Butchery adds Sulfur ore, and Iron's Spellbooks adds Mithril ore placement.
Other: Supplementaries places cave urns and wild flax in both biomes.
Mobs and structures
Both biomes spawn the vanilla monsters and animals plus a large set of Born in Chaos mobs. Spiders, skeletons, creepers and slimes carry the highest monster weight (100 each), followed by zombies (95). The Born in Chaos mobs have much lower weights, and the pack halved their spawn weights overall so they do not crowd out vanilla monsters. Dread Hounds and Bloody Gadflies are among them. Parrots have the highest passive weight in the Biomes O' Plenty Tropics (40), and tropical fish are the most common water ambient mob there (25). The Regions Unexplored Tropics adds sheep and cows to its passive list.
Both biomes contain many structures, 86 for Biomes O' Plenty and 106 for Regions Unexplored. These include a sparse jungle pillager outpost from Towns and Towers, Born in Chaos structures such as the Firewell, and vanilla mineshafts and buried treasure in the Regions Unexplored version.
The monster list is long and includes many Born in Chaos mobs. Carry light and weapons when travelling through either biome at night.
Zombie sieges do not spawn in either biome, and patrols do not spawn in the Biomes O' Plenty version. Wandering traders do not spawn in the Regions Unexplored version.
The Biomes O' Plenty Tropics carries the increased fire burnout tag, so fire there burns out more quickly.
Parrots, chickens and pigs are the main passive food sources. Parrots are the most common passive mob in the Biomes O' Plenty Tropics.
The rarity of both biomes means a trip to find one is usually a dedicated expedition. Use a biome finder such as Nature's Compass.