The perks menu sits on the left side of the screen, and each Gold spend works best when it answers a stage loss. Max Yen helps when placement money caps out too early. Yen Generation helps when a round lasts long enough that income speed decides whether the board stabilizes. Base Health helps when the run is mostly controlled but one leak or boss hit ends the stage.
Max Yen is the first perk for many new accounts because placement and upgrade timing decide early Story clears. If your team has a good unit but placement money is too low, more damage on paper does not change the run. A higher money cap gives you room to save for expensive placements and smoother upgrades, especially when a stronger unit costs more than your starter units.
Yen Generation comes next when income speed is the problem. If you can hold enough Yen but the stage moves too quickly for placements and upgrades, generation matters. This perk gains value in longer stages and modes where the board has time to scale. A frequently capped wallet points to Max Yen first. Slow income during the round points to Yen Generation next.
Base Health is a close-run perk. It fits runs where units handle most waves and one enemy slipping through ends the attempt. If bosses or full waves walk through the whole defense, health only delays the loss. That run needs damage, economy, traits, placement changes, or gear before more base health matters.
Early Gold belongs in the perk that changes the stage. Equal spending can leave the account with no solved problem. If the blocker is placement money, put the next Gold into Max Yen until that blocker changes. If the blocker becomes income timing, move to Yen Generation. If the blocker becomes one fatal leak, move to Base Health.
Each meaningful upgrade needs a stage test. After increasing Max Yen, replay the stage where a key unit entered too late. After increasing Yen Generation, watch whether placements and upgrades happen earlier. After increasing Base Health, see whether the leaked enemy still ends the run. If the perk does not change the loss, move the next Gold to the system that does.
Perks interact with summons, traits, and gear. A damage trait on a carry can reduce leak pressure because enemies die earlier. Gear on a damage unit can make income feel better because waves end faster. A farm or economy unit can change the value of Yen-related perks. Recheck perk priority whenever a new unit, trait, or gear piece changes how the stage plays.
Check the perk menu for the Gold cost before spending. Gold belongs where it unlocks the next clear. Hold Gold if you are about to test a new unit, because a better roster can change which perk matters. Story and farming content after each upgrade keep the account earning resources instead of staying in the upgrade menu.