# Sacred Pile — Design Tips

Authored by the game's maintainer. The contract (`/td/api/ai`) and the
stats reference (`/td/api/ai/guide`) describe what the server accepts
and how it behaves. This page is opinion-from-the-source — the
maintainer's design tips, not generated text.

## Wave 1

Wave 1 is usually a few easy mobs like `sewerRat` or `poopMinion`.

## Shitter tier-1 damage by placement

A Shitter tier-1 can deal roughly the following total damage to a dummy
mob moving at average speed, depending on placement:

- ~75 damage when placed next to a straight path.
- ~125 damage when placed in a corner.
- ~175 damage when placed in a U-turn.

## Designing each wave

For each wave, consider the number of mobs and the spawn interval
between them together. Estimate the expected number of towers the
player will have by that wave, then derive a mob count and `spacingSec`
(default `0.7`) that matches the player's expected firepower.

## Mob scaling reminder

Remember that mob HP increases with wave number, and their soul drop
increases as well — though more slowly than HP. The exact formula is in
the stats reference under "Per-wave mob scaling".

## Experience length

Decide total wave count from the target play time:

- **Short** (< 20 minutes): wave count < 10.
- **Medium** (20 minutes – 1 hour): 10 ≤ wave count < 35.
- **Long** (1 hour+): 35+ waves.

## Wave theme structure

Group waves in cycles: about **2–5 minor waves** containing at most
**4 mob types**, then a **boss wave** containing a boss.

Bosses per boss wave:

- **Below wave 15**: 1–2 bosses per boss wave.
- **Wave 15 and above**: more bosses allowed.

To strengthen a boss wave when needed, add mobs drawn from the same
4 types used in the preceding minor waves, before and/or after the
boss within the same wave entry list.

## Dangerous waves without a boss

Have some high-HP mobs first to attract fire, then release `poopEye`
(which move fast).

## Reference levels

No existing level is perfect, but every level in the **Official**
category is a good reference example. Fetch them with
`GET /td/api/levels` and filter the response for `isOfficial: true`.