About Knock Knock: Room Defense
Knock Knock: Room Defense is a gothic-chibi horror tower defense game, launched globally in September 2026. Each match lasts just 5 minutes — close the door, build your defense line, and survive the night.
The game blends tower defense, idle RPG, and horror atmosphere. Your bed generates Gold, your door holds back monsters, and your heroes fight back. With over 100 unique heroes and ghosts in a cute-but-creepy art style, you can explore haunted locations like ghost trains, midnight dormitories, and underground caves.
What's the Main Currency in Knock Knock: Room Defense?
Knock Knock: Room Defense Diamonds are the main premium currency. You can use Knock Knock: Room Defense Diamonds to summon heroes from the hero banner — 1 pull costs 250 Diamonds, and 10 pulls cost 2,200 Diamonds. Upgrading gear and many other things also require Gold and other materials, and Diamonds can be exchanged for all of them.
How to get Knock Knock: Room Defense Diamonds:
In-Game Rewards– Completing stages, clearing the Infinity Train, and finishing daily challenges reward you with Gold, Hero Contracts, and other items.
Promo Codes– The game regularly releases redemption codes that give free Diamonds. For example, the code knock2026 grants 100 Diamonds and 1,000 Soul Flame.
Why Do You Need Knock Knock: Room Defense Diamonds?
Knock Knock: Room Defense is free to play, but Knock Knock: Room Defense Diamonds are key to summoning powerful heroes and progressing faster — especially when you need to clear harder stages.
1. Summon Heroes
Knock Knock: Room Defense Diamonds let you pull from the hero banner. A single pull costs 250 Diamonds, and a 10-pull costs 2,200 Diamonds. With a wide roster of heroes, having enough Diamonds means you can build a stronger team and find the right synergies.
2. Speed Up Progression
Free players hit walls where progress slows down. Knock Knock: Room Defense Diamonds let you summon more heroes, unlock upgrades, and push further into the campaign.
3. Farm Gear and Resources
Knock Knock: Room Defense Diamonds can be used alongside other resources to farm gear and materials from the School Trip and other modes. Investing in Diamonds helps you keep your team battle-ready.
