Gameplay

Building a tower

Click an empty tile to open the build picker. Every tower costs 50 gold whatever you choose, and the picker asks for two things before you press Build:

1. A school — one of twelve. The tower takes that school's damage, range, fire rate and starting abilities, and joins its side of the counter web.
2. A path — A, B or C. Each school's three paths carry different roles and unlock ten upgrade slots.

Neither choice can be changed. Selling refunds half of everything you put into the tower, so a mistake costs you 50% rather than 100%. Selling takes two presses of S or the Sell button within three seconds.

Pause is look-only: while the game is paused you cannot build, upgrade, sell or start a wave.

Reading the HUD

• Top left: map name, route count, zoom and clock.
• Resources: gold and lives remaining out of the starting pool, then the wave and its progress bar. Between waves it shows the upcoming wave and BUILD.
• Progress: enemies still alive out of the wave's total, kills this run and the violet x for combos triggered.
• Defence: combined tower damage per second and towers standing. Pause, fast-forward and help are at the far right.
• Bottom panels: minimap and Start Wave on the left; build choices or the selected tower's upgrade slots and Sell button in the centre.
• Next-wave preview: bottom right, with its number, enemy total and counts by school. Check whether your towers counter what is coming.

The ten slots

Select a tower and the bottom panel lists its ten slots, numbered [0] to [9], with each one's level and the price of the next. Three slots are the same on all 36 paths: Damage, Attack Speed and Range. The other seven belong to the path and are listed on its Towers entry.

Each slot is levelled on its own and its cost multiplies per level — around ×1.45 to ×1.8, depending on the slot — which is why pouring gold into one tower gets expensive fast and why Megalith is reachable at all. Path slots cap out. Damage and Attack Speed never cap, but levels past 15 add nothing (they still count toward Megalith).

Waves

A wave sends 10 enemies plus half its wave number, rounded down. Every tenth wave is a milestone: 1.6× the enemy count, and the map's usual school bias is dropped so all twelve are equally likely — the wave your specialised defence is least ready for.

Enemy health multiplies by 1.09 per wave. After wave 25 a second ramp of 1.16 per wave stacks on top, which is where most runs end. Speed rises by 1.015 a wave, capped at 1.8×. Gold per kill rises by 1.06 a wave, so income grows far slower than the wall you are shooting at.

Enemies also gain traits as the waves climb — armour at 10, speed at 15, stealth at 20, regeneration at 25, healers at 30, magic shields at 35, and splitting on death at 40 — and from wave 50 every single enemy carries one to three of them. All seven are in the Bestiary.

Prepare for stealth from wave 20. Radiance can target hidden enemies; its first hit reveals that enemy for every other tower. Cover each route, but remember it reveals one target at a time. Splash damage can hit hidden enemies, and Holy Ground reveals enemies crossing it.

How towers choose what to shoot

A tower always fires at the enemy furthest along the path that is inside its range — never the closest, and never the weakest. Placement near the goal therefore means shooting at whatever is about to score, and placement near the spawn means first crack at a full wave.

Synergy, precisely

Two rules that sound like one and are not:

• Combos need two different schools to damage the same enemy within 1.5 seconds. The towers can be anywhere on the board. Only a tower’s own shot counts, and the splash from it — damage-over-time ticks do not register as a hit for this purpose, so two damage-over-time paths burning the same enemy will never set their pair off by burning alone. One of them has to land a shot. Each pair then goes on its own cooldown for that enemy — 4 to 15 seconds depending on the pair — and, on top of that, no enemy can take more than one combo of any kind per 1.5 seconds.
• Adjacency needs two different schools orthogonally next to each other — up, down, left or right, never diagonal. It grants stats regardless of what either tower shoots. Extra neighbours do not add damage or attack speed: the strongest bonus of each kind wins, including auras.

The adjacency figures on the Synergies pages are the values that reach play. The game stores larger damage and attack-speed numbers and applies 40% of them, and halves the strength of damage-type combo effects as well — both are balance dampers added after the tables were written.

Co-op

Up to six players share one board and one pool of lives over Steam. Each player has their own wallet and can upgrade or sell only their own towers. Extra players make both sides bigger:

• The shared lives start 30% higher per extra player.
• The starting gold gains 90 per extra player and is split evenly.
• Kill gold rises by 15% per extra player and is split evenly as enemies die.
• Enemies get more numerous (×N^0.58) and tougher (×N^0.60 health).

Lives and starting gold are fixed when the game is created, from the player count at that moment. The first wave starts itself after two minutes if nobody starts it sooner.

One player hosts and runs the simulation; the others mirror it, and a late joiner is caught up by a full state keyframe within about a second. Clients earn the wave and player-count writs. Untouchable, One True Path, Minimalist, Walking Compendium, Blitz, Megalith and Crucible go to the host only. Co-op games do not count toward World Tour, Veteran, Per-Map Bests or lifetime records at all; only solo runs do.

Controls

This is the game's own reference screen, key for key, plus the controller mapping.