What spawns in the River biome (Overworld)? 13 mobs with spawn weights, chances and group sizes for Java & Bedrock. Including Bat, Creeper and Drowned.
| Mob | Weight | Chance | Group size |
|---|---|---|---|
 Creeper |
100 | 16.3% | 4 |
 Drowned |
100 | 16.3% | 1 |
 Skeleton |
100 | 16.3% | 4 |
 Slime |
100 | 16.3% | 4 |
 Spider |
100 | 16.3% | 4 |
 Zombie |
95 | 15.4% | 4 |
 Enderman |
10 | 1.6% | 1–4 |
 Witch |
5 | 0.8% | 1 |
 Zombie Villager |
5 | 0.8% | 1 |
| Total weight 615 · 100% | |||
| Mob | Weight | Chance | Group size |
|---|---|---|---|
 Bat |
10 | 100% | 8 |
| Total weight 10 · 100% | |||
| Mob | Weight | Chance | Group size |
|---|---|---|---|
 Squid |
2 | 100% | 1–4 |
| Total weight 2 · 100% | |||
| Mob | Weight | Chance | Group size |
|---|---|---|---|
 Salmon |
5 | 100% | 1–5 |
| Total weight 5 · 100% | |||
| Mob | Weight | Chance | Group size |
|---|---|---|---|
 Glow Squid |
10 | 100% | 4–6 |
| Total weight 10 · 100% | |||
| Mob | Weight | Chance | Group size |
|---|---|---|---|
| Drowned |
100 | 50% | 1 |
| Slime |
100 | 50% | 1 |
| Total weight 200 · 100% | |||
| Mob | Weight | Chance | Group size |
|---|---|---|---|
| Glow Squid |
10 | 55.6% | 2–4 |
| Squid |
8 | 44.4% | 2 |
| Total weight 18 · 100% | |||
| Mob | Weight | Chance | Group size |
|---|---|---|---|
| Bat |
10 | 100% | 2 |
| Total weight 10 · 100% | |||
| Mob | Weight | Chance | Group size |
|---|---|---|---|
| Salmon |
16 | 100% | 3–5 |
| Total weight 16 · 100% | |||
Weight = spawn weight of the mob in its category · Chance = weight ÷ total weight of the category · Group size = how many spawn together.
In Java Edition 13 mob types can spawn in River — hostile mobs: Creeper, Drowned, Skeleton, Slime, Spider and Zombie and 3 more; ambient mobs: Bat; water mobs: Squid; fish: Salmon; underground water mobs: Glow Squid.
Creeper, Drowned, Skeleton and Slime share the highest spawn weight among the hostile mobs: 100 of 615 (16.3% each) in Java Edition.
Yes. Java Edition lists 13 spawn entries for River, Bedrock Edition 6. For example, Drowned has a weight of 100/615 (16.3%) in Java and 100/200 (50%) in Bedrock. Use the edition switch above the tables to compare.
Each spawn attempt first picks a category (for example hostile or passive mobs), then one mob of that category at random, weighted by its spawn weight. A mob's chance is its weight divided by the total weight of its category in the biome — so the shares in each table add up to 100%.
