Before the attempt
Save a layout that clears ordinary waves consistently. Avoid changing luck upgrades, placement, and object mix at once; a better result will not tell you which decision mattered.
During the attempt
Watch the first boss action that changes the run. Note whether the failure is durability, lane coverage, crowd pressure, or damage uptime. That observation becomes the next test.
After the attempt
Use relic and crafting screens in-game as the source of truth. Do not spend against a recipe copied from an undated video or another game. The official public description confirms the loop, but it does not publish a complete recipe table.
Verified fact: Slungpy Games describes powerful bosses with custom attacks and relics used to craft new objects. Community sources report a Wave 20 checkpoint; verify it after updates.