🌿 VeinSpread

by Moon Flower

Organic vein-based block spreading — like mycelium, sculk, or vines. A lightweight Paper/Spigot plugin for Minecraft 1.21+. Fully configurable via config.yml or in-game commands.

✨ Features

• Veins, not circles. Infection grows in winding lines with branches — like mycelium, sculk veins, or tree roots.
• Catalyst-driven. Place a catalyst block — and veins start crawling from it. Break it — growth stops, but the blocks that have already grown remain in the world.
• Full control. Step speed, vein length, branching frequency, direction "inertia", vertical branches, tip limit — everything is configurable.
• Replaceable blocks list. You decide what the vein is allowed to "eat". Use /vein blocks to see the current list.
• Time conditions. Veins can grow only at night, only during the day, or always.
• In-game management. The /vein command with tab-completion: change percentages, blocks, and speed without restarting the server. Changes are saved to the config immediately.
• Persistent growth. Active veins are saved to veins.json and seamlessly resume after a server restart.
• Localization. Player messages support both English and Russian out of the box.

🎯 Target Audience

• SMP servers looking to add a "living world" without mods or new dimensions.
• Lore-based survival — veins as an "infection", "curse", or "ancient corruption".
• Builders and decorators — beautiful organic patterns made of sculk or mycelium.
• Admins who need a customizable alternative to the sculk catalyst with flexible logic.

📦 Installation

1. Make sure you have Paper 1.21+ (or Spigot 1.21+) and Java 21.
2. Download VeinSpread-1.1.1.jar from the releases page on Modrinth or GitHub.
3. Place the .jar into the plugins/ folder on your server.
4. Restart the server.
5. Open plugins/VeinSpread/config.yml — or use /vein directly in-game.

⚙️ Quick Start

Minimal example: mycelium turns stone and dirt into mycelium, grows every 3 seconds, veins are 12 blocks long, branching chance is 25%.

vein:
  catalyst-block: "MYCELIUM"
  result-block: "MYCELIUM"
  replaceable-blocks:
    - "STONE"
    - "DIRT"
    - "GRASS_BLOCK"
  interval-ticks: 60
  tip-energy: 12
  branch-chance: 0.25
  persistence: 0.75
  max-branch-depth: 3
  vertical-branch-chance: 0.1
  max-tips-per-catalyst: 8

time-conditions:
  enabled: false

Place a mycelium block on stone — and step back. In a couple of seconds, you will see veins crawling across the stone.

🧩 Configuration

vein section

time-conditions section

🎮 Commands

All commands require the veinspread.admin permission (default is op).

Examples

/vein set branch-chance 30%
/vein set persistence 0.85
/vein set interval 60
/vein set tip-energy 20
/vein set vertical 5%
/vein set max-branch-depth 4
/vein set maxtips 12
/vein set catalyst-block MYCELIUM
/vein set result-block MYCELIUM
/vein addblock RED_SAND
/vein removeblock DIRT
/vein set time true
/vein set start-time 13000
/vein set end-time 23000

Percentages are accepted as 30%, 0.3, or 30 — the parser understands all three forms.

🔑 Permissions

🎨 Use Cases

Survival "Corruption"

vein:
  catalyst-block: "SCULK_CATALYST"
  result-block: "SCULK"
  replaceable-blocks: ["STONE", "DEEPSLATE", "COBBLESTONE", "GRAVEL"]
  interval-ticks: 120
  tip-energy: 25
  branch-chance: 0.15
  persistence: 0.85
  max-branch-depth: 2
  vertical-branch-chance: 0.05
  max-tips-per-catalyst: 4

time-conditions:
  enabled: true
  start-time: 13000
  end-time: 23000

At night, the corruption crawls across the stone; during the day, it freezes. Perfect for a "cursed biome".

"Living Forest"

vein:
  catalyst-block: "OAK_LOG"
  result-block: "MOSS_BLOCK"
  replaceable-blocks: ["DIRT", "GRASS_BLOCK", "STONE", "COBBLESTONE"]
  interval-ticks: 80
  tip-energy: 15
  branch-chance: 0.35
  persistence: 0.6
  vertical-branch-chance: 0.2
  max-tips-per-catalyst: 12

🛠️ Building from Source

git clone https://github.com/Moon-F1ower/VeinSpread.git
cd VeinSpread
mvn clean package

The compiled .jar will appear in target/VeinSpread-x.y.z.jar.
Requirements: Maven 3.9+, JDK 21.

❓ FAQ

Can I use it on Spigot instead of Paper?
Yes, but Paper is recommended — it was tested on Paper, and the 1.21 API is more stable there.

Does it work with WorldGuard?
Not yet — the plugin places blocks via Block.setType() without firing BlockSpreadEvent. WorldGuard won't see it. It's on the roadmap.

Are veins saved after a restart?
Yes! Active veins are saved to veins.json every 5 minutes and on server shutdown. They will seamlessly resume growing when the server starts again.

Can I have multiple catalysts with different settings?
In the current version — no, there is a single config for the server. Profiles by Material are on the roadmap.

Are thin veins (sculk veins, lichen) supported?
No, only full block replacement. It's on the roadmap.

Why aren't the veins growing?

1. The catalyst is placed (not just in the inventory).
2. Blocks in replaceable-blocks match by exact Material.
3. If time-conditions is enabled — it is currently the right time.
4. Chunks are loaded (a player is nearby).

🗺️ Roadmap

• Save active veins to disk (YAML/JSON) (Done in v1.1.0)
• In-game localization (English/Russian) (Done in v1.1.0)
• Support thin blocks (SCULK_VEIN, GLOW_LICHEN, VINE)
• Different catalyst profiles (Map<Material, Profile>)
• Light and biome conditions
• Fire BlockSpreadEvent for WorldGuard / GriefPrevention compatibility
• bStats
• BlockFadeEvent — "decaying" veins without a catalyst

📜 License & Source

This project is licensed under the MIT License — see LICENSE. Source code is available on GitHub: github.com/Moon-F1ower/VeinSpread

💬 Feedback

Found a bug or have a suggestion? Please open an issue on GitHub: github.com/Moon-F1ower/VeinSpread/issues

If you use the plugin on your server — I'd love to see screenshots in the Modrinth comments 🌿