Refresh README to match modern addon style

Drops the Alpha-stage notice, restructures the page with the same
section layout used by the recently-updated DimensionalTrees README,
and rewrites the configuration and replacement-rules sections to
reflect the current Nether / End / Overworld behaviour.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: tastybento

README.md

@@ -1,60 +1,118 @@
-# ExtraMobs Addon
+# 👾 ExtraMobs Add-on for BentoBox
 [![Discord](https://img.shields.io/discord/272499714048524288.svg?logo=discord)](https://discord.bentobox.world)
 [![Build Status](https://ci.codemc.org/buildStatus/icon?job=BentoBoxWorld/ExtraMobs)](https://ci.codemc.org/job/BentoBoxWorld/job/ExtraMobs/)
 
-Add-on for BentoBox that adjusts some mob spawning rules to get Blazes, Wither Skeleton, and Shulkers.
+## 🔍 What is ExtraMobs?
 
-## Where to find
+**ExtraMobs** is a BentoBox add-on that lets players spawn **Blazes**, **Wither Skeletons**, **Shulkers** and **Guardians** on their islands by building the right structures. It does **not** change Minecraft's spawning rules — it watches for natural spawns and replaces certain mobs by chance when the surrounding blocks match a themed pattern.
 
-Currently ExtraMobs Addon is in **Alpha stage**, so it may or may not contain bugs... a lot of bugs. Also it means, that some features are not working or implemented. 
-You can download it from [Release tab](https://github.com/BentoBoxWorld/ExtraMobs/releases)
+Works with every BentoBox game mode (AcidIsland, BSkyBlock, CaveBlock, SkyGrid, …).
 
-Or you can try **nightly builds** where you can check and test new features that will be implemented in next release from [Jenkins Server](https://ci.codemc.org/job/BentoBoxWorld/job/ExtraMobs/lastStableBuild/).
+---
 
-If you like this addon but something is missing or is not working as you want, you can always submit an [Issue request](https://github.com/BentoBoxWorld/ExtraMobs/issues) or get a support in Discord [BentoBox ![icon](https://avatars2.githubusercontent.com/u/41555324?s=15&v=4)](https://discord.bentobox.world)
+## 🚀 Getting Started
 
-## How to use
+1. Place the **ExtraMobs** `.jar` into your BentoBox `addons` folder.
+2. Restart your server.
+3. The addon creates `addons/ExtraMobs/config.yml`.
+4. Edit `config.yml` to adjust the spawn chances or disable specific game modes.
+5. Restart the server (or reload BentoBox) to apply your changes.
 
-1. Place the addon jar in the addons folder of the BentoBox plugin
-2. Restart the server
-3. In game you can change flags that allows to use current addon.
+---
 
-## Information
+## ✨ How Replacements Work
 
-This addon does not change Minecraft spawning rules. Instead it uses other mobs that are naturally generated and change their type with new entity, if all conditions are met.
+ExtraMobs only acts on **natural** spawns inside a BentoBox-managed world. When a candidate mob spawns on a themed block, ExtraMobs rolls against the configured chance; on success the original spawn is cancelled and the replacement entity is summoned in its place.
 
-##### For Wither Skeleton and Blaze:
+### 🔥 Nether — Wither Skeleton & Blaze
 
-Addon will replace Zombie Pigmen with Blaze or Wither Skeleton by chance from config, if:
- - given world is generated by GameMode Addon.
- - given world is Nether
- - Zombie Pigmen is standing on nether brick, nether brick slab or nether brick stairs.
+A **Zombified Piglin** or **Piglin** is replaced when:
+- the world is the BentoBox Nether,
+- and the mob is standing on **nether brick**, **nether brick slab**, or **nether brick stairs**.
 
-##### For Shulkers:
+The wither skeleton roll is checked first, then the blaze roll.
 
-Addon will replace Enderman with Shulker by chance from config if:
- - given world is generated by GameMode Addon.
- - given world is the End
- - Enderman is standing on purpur block, purpur stair or purpur slab. 
+### 🌌 End — Shulker
 
-##### For Guardians:
+An **Enderman** is replaced with a **Shulker** when:
+- the world is the BentoBox End,
+- and the mob is standing on a **purpur block**, **purpur slab**, or **purpur stairs**.
 
-Addon will replace Cod, Salmon or Tropical fish with Guardian by chance from config if:
- - given world is generated by GameMode Addon.
- - given world is the Overworld
- - biome in given location is deep ocean or any its variants
- - first block above water where fish is spawned is prismarine, prismarine brick or dark prismarine (blocks, slabs and stairs).     
+### 🌊 Overworld — Guardian
 
+A naturally-spawned **Cod**, **Salmon**, or **Tropical Fish** is replaced with a **Guardian** when:
+- the world is the BentoBox Overworld,
+- the biome is **Deep Ocean** (or Deep Cold / Deep Frozen / Deep Lukewarm),
+- and the first non-water block above the fish is **prismarine**, **prismarine bricks**, or **dark prismarine** (block, slab, or stairs variant).
 
-## Compatibility
+---
 
-- [x] BentoBox - 1.11.0 version
+## ⚙️ Configuration
 
-Addon is build on Minecraft 1.15.2 and BentoBox 1.11.0 version, however, it should even work on Minecraft 1.13.2 and BentoBox 1.0 Release.
+### Global Defaults
 
-Addon supports all Game mode addons.
+```yaml
+# Game modes in which ExtraMobs should not run.
+# Add the GameMode addon name (e.g. BSkyBlock, AcidIsland, CaveBlock).
+disabled-gamemodes: []
 
+nether-chances:
+  # Chance (0.0–1.0) to spawn a Wither Skeleton instead of a Zombified Piglin.
+  wither-skeleton: 0.01
+  # Chance (0.0–1.0) to spawn a Blaze instead of a Zombified Piglin.
+  blaze: 0.1
 
-## Information
+end-chances:
+  # Chance (0.0–1.0) to spawn a Shulker instead of an Enderman.
+  shulker: 0.1
 
-More information can be found in [Wiki Pages](https://github.com/BentoBoxWorld/ExtraMobs/wiki).
+overworld-chance:
+  # Chance (0.0–1.0) to spawn a Guardian instead of a fish.
+  guardian: 0.1
+```
+
+All chance values are decimals between `0.0` (never) and `1.0` (always). For the Nether the wither skeleton roll is evaluated before the blaze roll, so the blaze chance is effectively conditional on the wither skeleton roll failing.
+
+### Per-Gamemode Overrides
+
+You can define replacement rules that only apply to a specific game mode. Each gamemode may set rules for the `nether`, `end`, and/or `world` (overworld) environments. **When per-gamemode rules are present for an environment, the global defaults above are not applied for that gamemode.**
+
+```yaml
+gamemode-settings:
+  BSkyBlock:
+    nether:
+      - old: ZOMBIFIED_PIGLIN
+        new: WITHER_SKELETON
+        chance: 0.05
+      - old: ZOMBIFIED_PIGLIN
+        new: BLAZE
+        chance: 0.1
+    end:
+      - old: ENDERMAN
+        new: SHULKER
+        chance: 0.3
+    world:
+      - old: COD
+        new: GUARDIAN
+        chance: 0.15
+  AcidIsland:
+    end:
+      - old: ENDERMAN
+        new: SHULKER
+        chance: 0.5
+```
+
+Each rule needs:
+- `old` — the EntityType name of the mob to replace (e.g. `ZOMBIFIED_PIGLIN`, `ENDERMAN`, `COD`).
+- `new` — the EntityType name of the replacement (e.g. `WITHER_SKELETON`, `SHULKER`, `GUARDIAN`).
+- `chance` — probability in the range `0.0`–`1.0`.
+
+The gamemode key must exactly match the GameMode addon name as registered in BentoBox (`BSkyBlock`, `AcidIsland`, `CaveBlock`, `SkyGrid`, …). Themed-block requirements (nether brick / purpur / prismarine) still apply to per-gamemode rules.
+
+---
+
+## 🐛 Bugs and Feature Requests
+
+Please submit issues at [GitHub Issues](https://github.com/BentoBoxWorld/ExtraMobs/issues) or ask in the [BentoBox Discord](https://discord.bentobox.world).
+
+More information is available on the [Wiki](https://github.com/BentoBoxWorld/ExtraMobs/wiki).