Starter Units: What Opens a Room

What this page helps you decide: which unit to place first, and how much of your opening money to spend on it

The unit you place first is doing a different job from every unit after it. It is not there to clear the room; it is there to stop leaks cheaply while the early waves pay for the board that will. Getting this wrong is one of the most common reasons a run with a good team still fails.

The opening unit is buying time, not damage

Community clears of the hardest rooms describe the same opening: one durable unit holding the front line while money accumulates. The named examples vary by roster - Hell Kitten holding the Playground on Horror Mode, Hell Kitty at the front corners in the Kitchen and Bedroom - but the role is identical. What makes a unit good here is that it keeps working at low investment. A unit that only performs once fully upgraded is a bad opener no matter how strong it eventually becomes, because you cannot upgrade it during the waves where you need it. The guides make this explicit: a strong Mythic is a fine starter, and the point is durability rather than tier.

Spending everything early is the classic mistake

The instinct to place your best unit immediately fails for a specific reason. Early waves generate the income that funds the rest of the room, and an expensive unit at wave one is an unupgraded expensive unit for the next ten waves - performing like a weak one while leaving you nothing to react with. In long rooms this is worse, not better: with 21 waves before the boss there is ample time for compounding, so the cost of stalling your economy at the start is paid back with interest against you. Open cheap, let the waves fund the board, then place the units that matter.

Where the opener stands

Openers go where enemies arrive first and bunch up - the front corners of the walkway, the bend closest to the entrances, or between two entrances if the room has them. The goal is contact time rather than coverage, because at this stage there is nothing behind it to catch leaks. Later, as the real board fills in, the opener stops being the line and becomes the softening layer, which is exactly what a cheap durable unit should be doing by then. That progression is why the position that suits it early still suits it late.

What replaces it

The documented late boards look similar across very different rooms: area units where lanes converge, a beam unit on the longest path, and heavy single-target damage deep toward the exit. One Floor 4 clear used Torment, Demon Prince, The Duchess, Deaf Gunner and Demon Cat - a deliberate mix of area, beam, long range and heavy single target rather than five of the strongest. Horror Mode clears lean on Forbidden units such as Grave Cravers, frequently several, with one maxed rather than all partly upgraded. The consistent lesson is that the opener is temporary and the board that replaces it should cover four roles, not repeat one.

Step-by-Step

1. Open with a cheap durable unit whose value does not depend on being upgraded.
2. Place it where enemies arrive first and bunch - front corners, bends, between entrances.
3. Let the early waves fund the board rather than spending everything at wave one.
4. Replace it with a four-role board: area, beam, long range, heavy single target.
5. Max one heavy hitter rather than partly upgrading three.

Data Tables

Figures are player-reported in community video HiRjZQ3VAqc by Rubenakayoshii, not developer-published. Ratios, shares and expected values are our own arithmetic on those figures. Checked 2026-08-27.

Tips & Notes

FAQ

Opener job

Buy time, not damage

Board roles

4 (area, beam, range, single target)

Upgrade rule

Finish one before starting another

Checked

2026-08-27