- QUESTION 01What is Merge Defense?
- Merge Defense is a free browser tower defense game where you place and merge towers to stop waves of enemies. It features 7 base towers, 21 combo towers, a 3D wasteland and leaderboards. Signed-in accounts also unlock idle bases, the Workshop and invasions.
- QUESTION 02Do I need to install anything or create an account?
- Play free in your browser with no installation. Enter a commander name on the first screen to start as a guest. Online guests can submit a leaderboard score at game over. Coin, the Workshop, idle bases, invasions and defense history require signing in with GitHub or Kakao.
- QUESTION 03Can I play on mobile?
- Mouse and touch controls support desktop and mobile browsers. The 3D battlefield requires a WebGL2-capable browser and graphics acceleration. If performance is low, choose Medium or Low in the Graphics menu. Frame rate depends on your device and the battlefield.
- QUESTION 04Are Korean and English supported?
- Both the game and the public guide, tower combinations and FAQ are available in Korean and English. Use the language button on the first screen or the EN / 한국어 link at the top of each document. Documentation links from the English game open the English pages.
- QUESTION 05How do I save and resume progress?
- From wave 3, signed-in accounts save the towers and resources of the latest cleared checkpoint to the server every 30 seconds of real time. The game also attempts a save when entering idle mode and at game end. Use Resume Base on the first screen to return to the last server-confirmed checkpoint. Progress after that checkpoint may be lost if the connection or save fails, so check the in-game save status. Use the same account on other devices.
- QUESTION 06Does merging always increase a tower’s level?
- The same type at the same level gains one level. Different base types at the same level form a combo at the ingredient level. For example, Bow Lv.1 + Bow Lv.1 → Bow Lv.2, while Bow Lv.1 + Laser Lv.1 → Rail Arrow Lv.1. Different levels cannot merge. Different combo types cannot create a new combination.
- QUESTION 07What is the difference between Gold and Coin?
- Gold comes from enemy kills and cleared waves in the current run. Spend it on summoning, upgrading and awakening towers, among other run features. Coin comes from idle production, invasion bonuses and defense rewards on a signed-in account, and funds permanent Workshop upgrades. Account Coin and Workshop upgrades remain when you start a new game. Simply ending a normal run does not award Coin.
- QUESTION 08Do I automatically earn idle rewards when I close the browser?
- Sign in and queue idle mode first. From wave 3, with at least one tower placed, queue idle mode and clear the current wave to turn the base idle. Your base then produces Coin instead of continuing normal combat. Closing the browser alone does not activate idle mode.
- QUESTION 09Can idle Coin accumulate without a limit?
- The default storage cap is 4 hours. Production stops accumulating when storage is full. Supply Depot research increases storage time, and Base Crew research increases production. After Auto Collection Drone research, full storage can be collected automatically up to twice per day while the base keeps operating. The quota resets at midnight Korea Standard Time; offline collections settle when you reconnect.
- QUESTION 10Does an invasion destroy the other player’s base?
- Invasions use a copy of a saved base, so original towers and field devices are not consumed. An invasion with a Coin entry cost refunds that cost on success and may award a bonus; failure loses the entry cost. You can test your own base with free training, which does not affect Coin or win/loss records.
- QUESTION 11What if combat is slow or the 3D view does not appear?
- Choose Medium or Low in the Graphics menu and lower the game speed. If the 3D view is missing, check browser WebGL2 support and graphics acceleration. If the graphics context is lost, combat pauses and resumes after recovery. Check the save status before closing or refreshing the tab.
Explore the rules and recipes
The game guide covers controls and progression. Visit tower combinations for all 7 base towers and every combination recipe.