One True Path · Pyrewarden · Morass Games Wiki

One True Path
Reach wave 30 with all towers from a single school.

This one counts schools, not types — and it counts the towers standing, not the ones you have built. All three paths of one school still count as one school, and unlike Minimalist, selling a stray tower really does fix the run. The check is on the wave you clear, so you only need the board clean at that moment.

It also means no synergy combos at all. A combo needs two different schools to hit the same enemy, so a single-school defence gives up the mechanic the game is built around. Everything has to come out of raw upgrades.

Which school

Radiance, path A. The same reason as the two-type run and one more:

Stealth arrives at wave 20 and Radiance is the only school that can target it. Every other single-school run has a hard ceiling five waves short of the writ.
Radiance opens at 4.0 range — the longest in the game, tied with Chronomancy — so each tower covers more of the route, which matters when you have no second school to cover the gaps.
Path A blends area damage, support and damage over time, so one tower type still does more than one job.

The run, in order

Start on Wanderer's Waypoint. Do not pick a map that leans a school Radiance is weak to — Radiance is beaten by Toxicology and Voltomancy, and a map weighted toward either is 0.7× damage on most of what arrives.
Build Radiance and only Radiance. There is no adjacency bonus to chase here, since that needs two different schools, so place purely for route coverage.
Level Damage, Attack Speed and Range across the whole line rather than deep into a few towers. With no combos, throughput is the only lever you have.
Clear wave 30 with nothing but Radiance standing.

The recorded run

One game on a fresh profile, Wanderer's Waypoint, seed 4. It cleared wave 30 and ended in wave 31 with 74 towers, all of them Radiance.

Wave 5 with a line of Radiance towers along the route — Wave 5. One tower shape on the whole board, and it stays that way.

Wave 30 with dozens of Radiance towers and no other school — Wave 30, the qualifying wave. Open the image — every tower is the same mesh.

The in-game achievements screen showing One True Path unlocked — The same profile's ledger. One True Path is lit and nothing else is.

What breaks it

A tower of a second school standing when the wave clears. Sell it before the wave ends and the run is fine again.
Reaching wave 30 but not clearing it.
Choosing any school but Radiance and expecting to get past wave 20 once stealth starts.