> ## Documentation Index
> Fetch the complete documentation index at: https://cambridgebattlecode-mintlify-api-updates-1773706170.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.
# Builder Bot
> The only mobile unit — responsible for constructing all buildings.
Builder bots are the **only mobile unit**. They construct buildings, heal friendly entities, and can self-destruct for area damage.
## Properties
| Property | Value |
| -------------------- | ----- |
| HP | 30 |
| Base cost | 10 Ti |
| Scaling contribution | 10% |
| Vision radius² | 20 |
| Action radius² | 2 |
## Movement
Builder bots can move to an adjacent tile (including diagonals) if their move cooldown is 0. Moving increases the cooldown by 1.
Builder bots can **only walk on**:
* Conveyors (any variant, any direction, either team)
* Roads (either team)
* The allied core
These are called **walkable** tiles. The direction of the conveyor does not matter, and neither does the presence of resources on the tile.
```python theme={null}
# Move towards a target
direction = c.get_position().direction_to(target)
if c.can_move(direction):
c.move(direction)
```
## Actions
When action cooldown is 0, a builder bot can perform one of:
### Build
Build any building or turret on a tile within action radius that doesn't already have a building.
Only walkable buildings (conveyors and roads) can be built on a tile that contains a builder bot.
### Heal
Heal all friendly entities on a tile within action radius by **10 HP**.
```python theme={null}
if c.can_heal(target_pos):
c.heal(target_pos)
```
### Destroy
Destroy any allied building within action radius. This can be done **any number of times per round** and does **not** cost action cooldown.
```python theme={null}
if c.can_destroy(building_pos):
c.destroy(building_pos)
```
## Self-destruct
A builder bot can self-destruct at any time, dealing **20 damage** to the building on the tile it is standing on.
```python theme={null}
c.self_destruct()
```
## Markers
Builder bots (like all units) can place one [marker](/spec/other-buildings#marker) per round within action radius, separate from the action cooldown.