Survive The Night Tower Upgrades and Door-Tier Requirements
Improve a useful Survive The Night attacker, resolve its door-tier gate and focus damage spending on a tower that already covers the entrance.
Survive The Night tower upgrades are tied to door-tier progression. Improve an attacker that covers the doorway fight, and upgrade the door when its tier blocks the structure improvement you want.
Why a Tower Upgrade Can Be Locked
Higher tower and economy upgrades depend on the door tier. If the intended attacker upgrade is blocked by that requirement, invest in the door and then return to the tower. The door purchase opens access; the attacker purchase supplies the damage improvement you were planning.
Offensive tower upgrades increase damage and change the tower's appearance. Keep the objective concrete: you are improving an attacker because it contributes to the enemies your house faces. The visual change is a result of upgrading, not the main reason to spend.
Improve an Attacker That Covers the Threat
| Choice | Purpose | Next action |
|---|---|---|
| Attacker already covers entrance | Develop effective damage | Improve that tower |
| Door tier blocks upgrade | Open the intended structure tier | Upgrade door and return |
| Reach does not fit the fight | Fix the role or layout choice | Compare another damage option |
Concentrate the next damage purchase on an attacker doing a useful job at the entrance. Equal spending across every structure is less purposeful than strengthening the one responding to the current threat. If a short-range tower does not reach the fight, reconsider its role in the layout before assuming more investment solves the problem.
A Crossbow upgrade develops the opening ranged defense. Mortar contributes concentrated heavy-target damage, while Flamethrower depends on close coverage. Choosing among them is a role decision as well as an upgrade decision.
Keep the Rest of the Defense Working
Watch the door while investing. Manual repairs help sustain it during enemy pressure, and Medical Base provides in-range healing support. Those needs remain relevant while you strengthen attacking towers.
When the entrance holds but later purchases are hard to afford, improve Farm or Money Printer income toward the next useful upgrade. When the entrance is already threatened, direct available spending toward survival instead of expanding income indefinitely.
For the next run, keep a focused plan: one useful attacker upgrade, the door requirement it needs and the income that funds it. Read door upgrades for the progression gate or tower comparison for the role choice.