PotionCombine

A water cauldron. A handful of ingredients. A bit of patience.
PotionCombine turns vanilla cauldrons into a configurable brewing system: players shift-click ingredients into water,
wait for the brew to finish, then right-click the floating result. No GUI, no NMS, no command-block feeling.
Important: this is a Paper plugin. Spigot / CraftBukkit are not supported.
Requirements

• Paper 1.20.4 - 1.21.x
• Java 17
• PlaceholderAPI optional

What it does

• Brew custom potions directly inside vanilla cauldrons.
• Use shapeless recipes: ingredient order does not matter.
• Use vanilla items, potion types, and even other PotionCombine recipes as ingredients.
• Show live brewing progress with floating displays and particles.
• Let finished potions hover above the cauldron until collected.
• Optionally spoil unattended brews.
• Support custom sounds, particles, potion colors, effects, lore, and names.

New in 1.2.0
PotionCombine 1.2.0 is the cauldrons-talk-to-each-other release.

• Brewing chains: a finished potion can pour into a neighbouring cauldron if that result completes a higher-
  tier recipe.
• Downstream wait: a cauldron that is one ingredient short can wait for a nearby brew instead of failing
  immediately.
• Area heat: heat sources can count from around the cauldron, not only directly underneath it.
• Shared idle ticker: polluted cauldrons now use one shared idle loop instead of one task per dirty cauldron.
• API additions: new cancellable BrewChainEvent and PotionCombineAPI.synergyEnabled().

All 1.2 features are opt-in where they should be. Existing 1.1 setups keep behaving the same until you enable synergy
or area heat in config.
How players use it

1. Place a cauldron and fill it with water.
2. Hold an ingredient.
3. Shift + left-click the cauldron to insert it.
4. Shift + right-click to pull the last ingredient back out, if retrieval is enabled.
5. Wait for the brew to start.
6. Right-click the finished floating potion to collect it.

Configurable systems

• Recipes and custom potion effects
• Brewing time and grace period
• Overbrew / spoil timer
• Pollution and brush cleaning
• Heat source bonuses
• Hopper auto-extract
• World whitelist / blacklist
• Per-player cooldowns
• Nearby failure notifications
• Sounds and particles
• Progress bar MiniMessage template
• English and Russian language files

Commands
Aliases: , Permissions
PlaceholderAPI
If PlaceholderAPI is installed, PotionCombine registers the expansion automatically.
Notes before going live

• Live brew loops do not survive a hard server crash yet. Pollution persists; active ingredients are safely dropped
  on normal shutdown.
• Synergy checks only the four horizontal neighbouring cauldrons.
• Area heat uses the strongest source in range, not the sum of all sources.
• Hopper extraction collects finished potions immediately and bypasses the spoil timer.
• The bundled recipes are examples. Replace them with your own server recipes.

PotionCombine is built for servers that want brewing to feel like it belongs in vanilla: physical, readable,
configurable, and not trapped behind a GUI.