Knock Knock: Room Defense – Infinity Train Station Survival Tactics for Floors 407-410

Surviving the higher levels of the Infinity Train Station in Knock Knock: Room Defense requires precise resource management and structural efficiency. Floors 407 through 410 represent a significant spike in ghost aggression, forcing players to balance rapid building upgrades with consistent gold generation.

Priority Upgrades for Floors 407-410

As you progress through these specific floors, the ghosts become significantly more persistent. To hold your ground, prioritize your investments in the following order:

• Bed Leveling: Ensure your bed is upgraded early to maximize your "Gold per Second" (GPS) income. Without a high-level bed, you will fall behind on building repairs.
• Door Reinforcement: The door is your primary shield. If the ghost’s damage output begins to outpace your repair speed, focus all available gold into upgrading the door’s structural integrity before adding new defensive equipment.
• Defensive Turrets: Position your turrets strategically to ensure overlapping fields of fire. By floor 407, a single turret is rarely enough to deter the ghost from hovering near your door.

Resource Management Strategy

At this stage of the Infinity Train Station, wasting gold on unnecessary furniture can lead to an early loss. Follow these tactical rules for floors 407-410:

Surviving the Ghost Assault

The ghosts encountered between floors 407 and 410 exhibit increased speed and resilience. Use these tactics to manage the pressure:

1. Don't Panic Repair: If the ghost is actively attacking, keep your cursor ready on the door repair button, but only press it when the door health bar flashes red or dips below the danger threshold to save on repetitive clicking.
2. Strategic Idle Positioning: If you find yourself struggling to keep up with the repair demands, consider upgrading your door's "Auto-Repair" passive if available through your current character build.
3. Gold Accumulation: If you reach a point where the ghost has retreated, immediately dump your excess gold into your most expensive current upgrade to maximize efficiency before the next wave arrives.

By maintaining a strict balance between your GPS income and your defensive structural integrity, you can clear these floors consistently. Always keep a close eye on the door’s health bar—the transition between floor 409 and 410 often features a brief lull, which is the perfect time to finalize your highest-cost upgrades before the final assault.