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Gym Leaders & Custom Battle Arenas Guide

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Enzo1990-ui edited this page Oct 17, 2026 · 1 revision

Cobblemon Colonies: Gym Leaders & Custom Battle Arenas Guide

Welcome to the comprehensive guide for building, scanning, customizing, and battle-testing custom Gym Arenas in Cobblemon Colonies!

Table of Contents

  1. Overview
  2. Building & Scanning Custom Arenas
  3. Datapack Distribution & File Layout
  4. Radical Cobblemon Trainers (RCT) Integration
  5. Structurize Blueprint Integration & Safety Guarantees
  6. Linking Custom Blueprints to Custom NBT Arenas
  7. Complete Catalog of All 75 Mod Gym Leaders

1. Overview

Cobblemon Colonies enables players to create their own custom Gym Arenas in Creative or Survival mode, save them directly to world datapacks, and immediately challenge them through the Battle Arena building GUI.

Key features include:

  • In-Game Scanner: Select corners and preview bounding box dimensions in real-time.
  • Dynamic Sizing: The Gym building reads the exact NBT bounding box from the structure file and centers the arena in the pit.
  • Automatic Block Clearance: When a match finishes, a player leaves, or the arena times out, all placed arena blocks are automatically erased back to air with zero leftover blocks.
  • Datapack Auto-Discovery: Drop any .nbt arena file into a datapack and it will instantly populate the "Custom Arenas" dropdown in the Gym window.
  • Radical Cobblemon Trainers (RCT) Integration: Dedicated RCT tab with Series selection (Radical Red, BDSP, Unbound, and custom datapack series), active league progress tracking, automatic party healing after each victory, and gauntlet queues.

2. Building & Scanning Custom Arenas

The Gym Arena Scanner Item

The Gym Arena Scanner (cmoncol:arena_scanner) is available in the Cobblemon Colonies Creative Tab or via:

/give @p cmoncol:arena_scanner

Controls:

  • Left-Click Block: Sets Corner 1 (Pos 1). Block breaking is canceled.
  • Right-Click Block: Sets Corner 2 (Pos 2).
  • Sneak (Shift) + Right-Click: Clears the current selection.
  • Hover Tooltip: Displays your currently selected corners and total dimensions $(W \times H \times L)$.

Setting the NPC Spawn Point (Observer Block)

When Cobblemon Colonies loads your arena, it scans the structure for a minecraft:observer block:

  • Face direction / placement: Place an Observer block in your arena at the position where you want the Gym Leader and RCT Trainers to stand.
  • The NPC will spawn directly on top of the Observer block (Y + 1.0).
  • Note: If no Observer block is found, the mod automatically calculates the exact center floor of the arena.

Saving Your Arena via Command

Once you have selected Corner 1 and Corner 2 with the Arena Scanner, execute:

/cmoncol save_arena <arena_name> [leader_id] [rct_trainers]

(Alternative alias: /cmoncol arena save <arena_name> [leader_id] [rct_trainers])

Parameters:

  • <arena_name>: The unique file name (e.g. molten_pit, sky_pillar, dojo). Underscores and numbers supported.
  • [leader_id] (Optional): Any of the 75 mod Gym Leaders (e.g. blaine, brock, sabrina). Defaults to supporter.
  • [rct_trainers] (Optional): Comma-separated list of Radical Cobblemon Trainers IDs to battle sequentially before the leader (e.g. youngster_joey,camper_liam,blackbelt_kenta).

Other Arena Commands:

  • /cmoncol arena list: Lists all currently loaded built-in and datapack arenas, including dimensions, leaders, and RCT trainer counts.
  • /cmoncol arena scan <x1> <y1> <z1> <x2> <y2> <z2>: Manually sets scanner corners via coordinate input.
  • /gym reset <x> <y> <z>: Force-resets a Gym building, evicts players, despawns NPCs, and clears all arena blocks.

3. Datapack Distribution & File Layout

File Locations

When saving an arena via /cmoncol save_arena, the game automatically creates:

<world>/datapacks/custom_gyms/
├── pack.mcmeta
└── data/
    └── custom/
        ├── structure/
        │   └── structures/
        │       └── molten_pit.nbt
        └── gym_arenas/
            └── molten_pit.json

Custom arenas can also be packaged into standard Minecraft datapacks in:

  • data/<namespace>/structures/gym_arenas/<name>.nbt
  • data/<namespace>/structure/structures/<name>.nbt
  • data/<namespace>/structures/<name>.nbt

Companion JSON Format

To customize the display name, assigned Gym Leader, or RCT trainer gauntlet without re-saving the NBT file, edit <name>.json:

{
  "name": "Molten Volcano Arena",
  "leader": "blaine",
  "rct_trainers": [
    "youngster_joey",
    "camper_liam",
    "firebreather_dick"
  ]
}

4. Radical Cobblemon Trainers (RCT) Integration

Cobblemon Colonies features deep, first-class compatibility with Radical Cobblemon Trainers (rctmod) and the RCT API.

Dedicated RCT Tab & Series Selection

When RCT is installed, the Battle Arena GUI exposes a dedicated RCT mode tab alongside Gyms and Custom:

  • Series Dropdown: Allows players to choose which challenge league to embark on:
    • Active Series / League: Dynamically connects to the player's current active RCT league and automatically displays their next undefeated opponents.
    • Brilliant Diamond / Shining Pearl (BDSP): Sinnoh RCT leaders (Roark, Gardenia, Maylene, Crasher Wake, Fantina, Byron, Candice, Volkner).
    • Radical Red: Radical Red difficulty gym leaders (Brock, Misty, Lt. Surge, Erika, Koga, Sabrina, Blaine, Clair).
    • Unbound: Pokémon Unbound difficulty gym leaders (Mirskle, Vega, Alice, Mel, Galavan, Big Mo, Tessy, Benjamin).
    • Custom Datapack Series: Any additional series and leagues provided by installed RCT datapacks are automatically discovered and added to the series dropdown.

Active League Progress & Undefeated Opponents

  • When selecting Active Series, the mod queries the player's personal RCT PlayerState.
  • Trainers and leaders that the player has already defeated are automatically filtered out, ensuring the dropdown only displays opponents the player has yet to conquer.
  • Defeating an RCT Gym Leader in the arena updates the player's defeat records (addProgressDefeat and addDefeat), unlocking higher level caps and next-tier challenges in RCT.

Automatic Party Healing

  • In championship and gauntlet matches against RCT trainers and leaders, the player's entire Pokémon party is automatically and fully healed after every victory.
  • This ensures trainers are ready for consecutive multi-trainer gauntlets or post-battle exploration without tedious trips to a Pokécenter.

Official RCT Battle Arena (giovanni.nbt)

  • All direct RCT challenges use the official championship arena structure (giovanni.nbt) by default, offering a balanced, spacious battleground designed for high-level tactical AI play.

Custom Arena Apprentice Gauntlets (rct_trainers)

You can also integrate RCT apprentice trainers into your own custom player-made or datapack arenas:

  1. When a player challenges a custom arena with rct_trainers configured in its companion .json, the arena doors open and Trainer 1 is summoned.
  2. The player battles Trainer 1.
  3. Upon defeating Trainer 1, victory is announced in chat, the player's party is healed, and Trainer 2 is summoned.
  4. Once all apprentice trainers are defeated, the mod announces:
    "All Gym Trainers defeated! The Gym Leader steps forward!"
  5. The designated Gym Leader spawns for the final championship showdown!
  6. If RCT is not installed, the apprentice gauntlet is cleanly bypassed and the Gym Leader spawns directly.

5. Structurize Blueprint Integration & Safety Guarantees

Zero-Damage Guarantee for Existing & Custom Gyms

A common concern with dynamic sizing is whether loading an arena or cleaning up blocks could accidentally delete parts of the Gym building (e.g., walls, spectator stands, or roof).

Cobblemon Colonies guarantees 100% building safety through strict boundary clamping:

  1. Structurize Blueprint Tags:
    • structure_a & structure_b: Placed at opposite floor corners of the arena pit. The mod dynamically reads these to determine holeMinX..holeMaxX, holeMinZ..holeMaxZ, and holeMinY.
    • door_a & door_b: Placed at the entrance doorway. When a battle starts, this volume fills with air (open); when a battle ends or resets, it fills with oxidized copper blocks (closed).
  2. Strict Clearance Clamping:
    • When clearArenaBlocks() runs (on victory, defeat, timeout, or reset), the clear volume is strictly clamped within [holeMinX, holeMaxX] and [holeMinZ, holeMaxZ].
    • The clearing logic never affects blocks outside the pit walls or above the pit height.
    • The colony hut block and bedrock are always protected.
  3. Oversize Protection:
    • Before any arena is placed, the mod verifies that arenaWidth <= holeWidth and arenaLength <= holeLength.
    • If an arena is larger than the blueprint's designated pit, the battle is safely blocked with a warning message: "This arena is too large for this gym's pit."
    • This ensures an oversized arena can never overwrite building walls or spectator seating.
  4. Dynamic Pit Centering:
    • Because holeWidth and holeLength are calculated dynamically from structure_a and structure_b, custom gym blueprints with any pit size ($15\times 15$, $21\times 21$, $25\times 25$, $31\times 31$, etc.) automatically center any compatible arena at Y = holeMinY - 2.

6. Linking Custom Blueprints to Custom NBT Arenas

Minecolonies and Structurize allow server owners and datapack creators to design custom building style packs. Cobblemon Colonies offers two seamless ways to link custom Gym blueprints to specific NBT arenas:

Method A: In-Blueprint Structurize Tags (Recommended & Easiest)

When building your custom gym schematic in Creative mode:

  1. Place standard Structurize tags:
    • structure_a and structure_b at the pit floor diagonal corners.
    • door_a and door_b at the entrance doorway.
  2. Place an additional Structurize Tag Block (or use the Structurize Tag Tool):
    • Tag name: arena:<arena_id> (e.g. arena:brock, arena:custom_molten_pit, arena:pallete_water).
    • Or tag name: arena_link:<arena_id>.
  3. Export your schematic with the Structurize Scan Tool into your style pack.
  4. When a player opens the Battle Arena GUI, the custom arenas dropdown will automatically pre-select and link that arena!

Method B: Datapack Blueprint Link JSON (gym_blueprint_links/)

If you have existing blueprints and don't want to edit the .blueprint file, you can link them via a JSON file in your datapack:

Path: data/<namespace>/gym_blueprint_links/<pack_link_name>.json

{
  "structure_pack": "pallettown",
  "blueprint_path": "infrastructure/gym",
  "default_arena": "brock",
  "allowed_arenas": [
    "brock",
    "custom:molten_pit",
    "custom:boulder_field"
  ]
}

Fields:

  • structure_pack: Name of the style pack (e.g. pallettown, Combblemon Colonies Style, or your custom pack).
  • blueprint_path (Optional): Subdirectory or schematic name filter.
  • default_arena (Optional): The arena ID that auto-selects by default when opening the GUI in this building.
  • allowed_arenas (Optional): If specified, restricts the gym to only allow these specific arenas.

7. Complete Catalog of All 75 Mod Gym Leaders

Use these exact Leader IDs when saving arenas or configuring JSON companion files:

Gen 1: Kanto

Leader ID Name Type Specialty Badge Awarded
brock Brock Rock Boulder Badge
misty Misty Water Cascade Badge
surge Lt. Surge Electric Thunder Badge
erika Erika Grass Rainbow Badge
koga Koga Poison Soul Badge
sabrina Sabrina Psychic Marsh Badge
blaine Blaine Fire Volcano Badge
giovanni Giovanni Ground Earth Badge

Gen 2: Johto

Leader ID Name Type Specialty Badge Awarded
falkner Falkner Flying Zephyr Badge
bugsy Bugsy Bug Hive Badge
whitney Whitney Normal Plain Badge
morty Morty Ghost Fog Badge
chuck Chuck Fighting Storm Badge
jasmine Jasmine Steel Mineral Badge
pryce Pryce Ice Glacier Badge
clair Clair Dragon Rising Badge

Gen 3: Hoenn

Leader ID Name Type Specialty Badge Awarded
roxanne Roxanne Rock Stone Badge
brawly Brawly Fighting Knuckle Badge
wattson Wattson Electric Dynamo Badge
flannery Flannery Fire Heat Badge
norman Norman Normal Balance Badge
winona Winona Flying Feather Badge
tate Tate Psychic Mind Badge
liza Liza Psychic Mind Badge
tate_and_liza Tate & Liza Psychic (Dual Battle) Mind Badge
wallace Wallace Water Rain Badge
juan Juan Water Rain Badge
sootopolis Sootopolis Gym Water Rain Badge

Gen 4: Sinnoh

Leader ID Name Type Specialty Badge Awarded
roark Roark Rock Coal Badge
gardenia Gardenia Grass Forest Badge
maylene Maylene Fighting Cobble Badge
crasher_wake Crasher Wake Water Fen Badge
fantina Fantina Ghost Relic Badge
byron Byron Steel Mine Badge
candice Candice Ice Icicle Badge
volkner Volkner Electric Beacon Badge

Gen 5: Unova

Leader ID Name Type Specialty Badge Awarded
cilan Cilan Grass Trio Badge
chili Chili Fire Trio Badge
cress Cress Water Trio Badge
striaton Striaton Triplets Elemental (Random) Trio Badge
lenora Lenora Normal Basic Badge
burgh Burgh Bug Insect Badge
elesa Elesa Electric Bolt Badge
clay Clay Ground Quake Badge
skyla Skyla Flying Jet Badge
brycen Brycen Ice Freeze Badge
drayden Drayden Dragon Legend Badge
iris Iris Dragon Legend Badge
opelucid Opelucid Gym Dragon Legend Badge
cheren Cheren Normal Basic Badge
roxie Roxie Poison Toxic Badge
marlon Marlon Water Wave Badge

Gen 6: Kalos

Leader ID Name Type Specialty Badge Awarded
viola Viola Bug Bug Badge
grant Grant Rock Cliff Badge
korrina Korrina Fighting Rumble Badge
ramos Ramos Grass Plant Badge
clemont Clemont Electric Voltage Badge
valerie Valerie Fairy Fairy Badge
olympia Olympia Psychic Psychic Badge
wulfric Wulfric Ice Iceberg Badge

Gen 8: Galar

Leader ID Name Type Specialty Badge Awarded
milo Milo Grass Galar Grass Badge
nessa Nessa Water Galar Water Badge
kabu Kabu Fire Galar Fire Badge
bea Bea Fighting Galar Fighting Badge
allister Allister Ghost Galar Ghost Badge
stow_on_side Stow-on-Side Gym Fighting / Ghost Fighting / Ghost Badge
opal Opal Fairy Galar Fairy Badge
gordie Gordie Rock Galar Rock Badge
melony Melony Ice Galar Ice Badge
circhester Circhester Gym Rock / Ice Rock / Ice Badge
piers Piers Dark Galar Dark Badge
raihan Raihan Dragon Galar Dragon Badge

Gen 9: Paldea

Leader ID Name Type Specialty Badge Awarded
katy Katy Bug Paldea Bug Badge
brassius Brassius Grass Paldea Grass Badge
iono Iono Electric Paldea Electric Badge
kofu Kofu Water Paldea Water Badge
larry Larry Normal Paldea Normal Badge
ryme Ryme Ghost Paldea Ghost Badge
tulip Tulip Psychic Paldea Psychic Badge
grusha Grusha Ice Paldea Ice Badge

Special VIP Supporter

Leader ID Description
supporter VIP Supporter NPC with authentic player skins, cloaks, dynamic textures, and random Cobblemon team scaling to level 50.

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