Published game rules
The bench plays by one deterministic rulebook
A saved replay carries the game version it was played under, its starting board, and every move in order. That is what lets anyone watch it back exactly as it happened.
Core play rules
- Every placed tool occupies cells and can lengthen the ground route; diagonal corner gaps are not passable.
- Placements that block every active route or land on a creep are refused.
- Ground streams use the west and north gates. Flying waves cross dedicated air corridors and ignore the maze.
- Standard sales refund the full amount spent on the tool and its upgrades, except a spent Mousetrap follows its documented spent-state rule.
- Sending a wave early awards bonus gold. Several waves may overlap.
- A run clears only after its final campaign wave while pattern integrity remains above zero.
What is on the bench
- Campaigns
- 6 difficulties
- Tools
- 15 workbench towers
- Creeps
- 17 enemy types
The first three campaigns use staged introductions; post-Master campaigns use deterministic varied decks with specialists, relays, champions, armored air, and command bosses. See the campaign ledger and handbook for visible details.
Game versions
Every save records the game version it was played under. Only versions that are still open accept new submissions to the Leaderboard, and the server checks a save really was played under the version it names.
The open versions are listed by the rules versions API. This page describes the game as it stands today.
Guidance never becomes certification
How a run was played stays attached to it. Watching a build guide, or following one in Standard, does not turn the result into a Ranked Challenge. CERT belongs to a locked challenge run and nothing else.