Road, Barrier & Marker

Road

Walkable tiles for builder bots to move on. The cheapest building.

Property	Value
HP	4
Base cost	1 Ti
Scaling	0.5%

Barrier

Cheap, takes up space, and has high HP. Useful for blocking enemy paths or protecting key buildings.

Property	Value
HP	30
Base cost	3 Ti
Scaling	1%

Marker

A tile containing a single unsigned 32-bit integer that can be read by any allied unit. Building a marker is completely free and does not cost action cooldown — you may place at most one marker per round. Any team may build over markers, destroying them. Additionally, all units (core, builder bots, and turrets) can destroy friendly markers for free using the standard destroy action. Markers remain targetable by gunners, but unlike walls, builder bots, and non-marker buildings they do not block line of sight or shield occupied tiles behind them.

Property	Value
HP	1
Cost	Free

Markers are the only form of communication between allied units. Global variables are not shared between Player instances — each unit has its own isolated Python environment.

All units (core, builder bots, and turrets) can place markers — not just builder bots.

# Write a value to a marker
if c.can_place_marker(pos):
    c.place_marker(pos, 42)

# Read a marker
building_id = c.get_tile_building_id(pos)
if building_id is not None:
    if c.get_entity_type(building_id) == EntityType.MARKER:
        value = c.get_marker_value(building_id)

Communication patterns

Since each unit’s Player instance is isolated, markers are essential for coordination:

Scouting reports: Write enemy positions to markers near your core
Build orders: Use marker values as state machine flags
Territory claims: Mark tiles to avoid duplicate work

Overview

Units

Buildings

Combat

Reference

Road

Barrier

Marker

Communication patterns

​Road

​Barrier

​Marker

​Communication patterns

Road

Barrier

Marker

Communication patterns