Editing a game

The editor is guest-friendly: paint a map first, sign up when you want to keep it.

Map cells

• Spawn — monsters enter here (need at least one).
• Exit — monsters leave here (need at least one for most modes).
• Path — used by Monster March as the painted lane.
• Tower pad — preferred build sites for towers.
• Ground — open terrain (buildable if “allow ground build” is on).
• Wall — blocked cell for mazes (Monster Rush).

Tip: click a cell with the same palette tool selected to clear it back to ground.

Game types

• Monster March (monster_march)
• Monster Rush (monster_rush)
• Defend the Castle (defend_the_castle)

Monster March follows painted paths. Monster Rush pathfinds; when blocked, monsters attack the nearest wall/tower on the dig route (Chaos mode keeps smashing the shortest line). Defend the Castle focuses on a central objective.

Towers, monsters, waves

• Towers — cost, health, damage, range, cooldown, weapons, elements, and flat upgrades.
• Monsters — HP, speed, score reward.
• Wave types — which rounds run, monster groups, and scaling by appearance or round.

Guests have lower type caps; registered accounts get higher caps. Limits show in the editor header.

Publishing

• Public — shareable play link + gallery eligibility.
• Allow download — others can download the OpenTD JSON export.
• Use Dashboard to manage games, import JSON, and copy play links.