← Part 1: Basic Damaging Spell | Next: Part 3: Unit Stat Upgrades →

In this lesson, we’ll build a spell that grants a status effect to every unit (friendly and enemy) on an entire floor.

Our card, Give Everyone Armor, grants Armor 2 to all friendly and enemy units in the target room. Along the way, you'll learn how room-wide targeting works, how status effects are defined, and how to use localization replacement tokens for game keywords.

Download the custom card art:

• Download Art: GiveEveryoneArmor.png
• Save Location: Save it to your mod project under textures/GiveEveryoneArmor.png.

In Plugin.cs, add "json/spells/GiveEveryoneArmor.json" to your AddMergedJsonFile call. Then create json/spells/GiveEveryoneArmor.json and add:

{
  "$schema": "https://github.com/Monster-Train-2-Modding-Group/Trainworks-Reloaded/releases/latest/download/schema.json",
  "cards": [
    {
      "id": "GiveEveryoneArmor",
      "cost": 1,
      "names": {
        "english": "Give Everyone Armor"
      },
      "descriptions": {
        "english": "Apply [armor] [effect0.status0.power] to all units."
      },
      "rarity": "uncommon",
      "targets_room": true,
      "targetless": true,
      "class": "ClassBanished",
      "card_art": "@GiveEveryoneArmorCardArt",
      "pools": [
        "MegaPool"
      ],
      "effects": [
        "@GiveAllUnitsArmor"
      ]
    }
  ],
  "effects": [
    {
      "id": "GiveAllUnitsArmor",
      "name": "CardEffectAddStatusEffect",
      "target_mode": "room",
      "target_team": "both",
      "param_status_effects": [
        {
          "status": "armor",
          "count": 2
        }
      ]
    }
  ],
  "game_objects": [
    {
      "id": "GiveEveryoneArmorCardArt",
      "type": "card_art",
      "extensions": {
        "card_art": {
          "sprite": "@GiveEveryoneArmorSprite"
        }
      }
    }
  ],
  "sprites": [
    {
      "id": "GiveEveryoneArmorSprite",
      "path": "textures/GiveEveryoneArmor.png"
    }
  ]
}

In Part 1, we targeted a single character with an arrow. Here, we target the floor itself:

• targets_room: true & targetless: true: When dragged, the card highlights the room rather than displaying a directional targeting arrow toward an individual unit.
• target_mode: "room": Instructs the effect to target character in the room. With target_team we determine which team gets targeted.
• target_team: "both": Ensures the effect applies to both Monsters (friendly) and Heroes (enemies).

"descriptions": {
  "english": "Apply [armor] [effect0.status0.power] to all units."
}

• [armor]: A dynamic localization tag that automatically inserts the localized term for Armor in bold text.
• [effect0.status0.power]: Traverses the card's data structure to read the count (power) of the first status effect (status0) in the first effect of the card (effect0) (here, it will evaluate to 2).

"effects": [
  {
    "id": "GiveAllUnitsArmor",
    "name": "CardEffectAddStatusEffect",
    "target_mode": "room",
    "target_team": "both",
    "param_status_effects": [
      {
        "status": "armor",
        "count": 2
      }
    ]
  }
]

• name: CardEffectAddStatusEffect is the general-purpose effect that applies a status effect to the targeted units.
• param_status_effects: A list defining the status to apply:
  • status: The internal ID of the status effect. Note that internal IDs don't always match the lowercase display name (e.g., Quick is internally named ambush).
  • count: The number of stacks applied.
• param_int (optional): When using CardEffectAddStatusEffect, param_int acts as a percentage chance (0–100) to apply the effect. If omitted, it defaults to 100%.

1. Build your solution and verify the compiled mod output is in BepInEx/plugins/<YourMod>/.
2. Launch Monster Train 2 and check the BepInEx console log for clean startup with no errors.
3. Start a battle with several friendly and enemy units present in a room:
   • Verify the card displays the name Give Everyone Armor, costs 1 Ember, and shows the text: "Apply Armor 2 to all units."
   • Cast the card into the room: confirm that every unit on the floor—both allies and enemies—receives 2 stacks of Armor.

Now that you can apply status effects across floors, head to Part 3: Unit Stat Upgrades (Not Razorsharp Edge) to learn how to alter unit attack and health using CardUpgrades.