Atom Fusion is a building introduced in June 2013. Its purpose is to produce a more powerful unit from "fusing" 2 units, and getting a third (Usually Stronger) Unit. The player gets the two original soldier back and intact.
Two units for fusion: Place 2 units inside the building. You may select the units on the map, or inside Atom Fusion. It does not matter whether you put a unit on the left or right side in Atom Fusion since sometimes the units may switch places when you enter the building again. To view a list of possible combinations, see this list.
The silhouette: After some loading time from a few seconds to a minute, Atom Fusion will show the white silhouette of the unit you are going to get. You may try to speculate what kind of unit it is. You might get some ideas from Unit Collection in the game or from this wiki.
Getting the right one: If you are not satisfied with the silhouette, it is okay to withdraw the units and start again. Generally the stronger units you use, the stronger unit you will get. But even if you put the same 2 units in Atom Fusion over and over again, the resulting units (as seen from their silhouettes) often vary on multiple tries. It is possible to get a result which is a lot stronger than the 2 units you use. So just keep trying.
Fusing: If the silhouette seems okay to you, just click "Start Fusion" to activate the fusion and count-down clock.
Countdown: It then shows the countdown time to produce the new unit. It may take from half an hour to a few days to finish the process. There is no relation between the units you use for fusing and the unit you are going to get. For instance, selecting 2 aircraft units for fusion does not mean that you are any more likely to get a new aircraft unit than others. One case suggests that the stronger the units you use, the more time it takes to get the new unit. For instance, to get a Godzilla Mech, it takes 4 days 6 hours and 10 minutes from fusing King Kong Mech and Laser Blade, while it takes 5 days 4 hours and 20 minutes from fusing King Kong Mech and Red Mercury Dragon. Another case suggests that the fusing time only relates to the new unit produced. For instance, to get a Massive Gunner Mech, it takes 5 days 10 hours and 5 minutes whether from fusing King Kong Mech and Dual Blade Automech or fusing King Kong Mech and Fire Godzilla Mech.
Done: After the countdown is finished, enter the building and click "Get Unit".
Cash: While it is not recommended to instantly finish the fusion by paying cash. The units you use may or may not have relation to the time it takes to fuse a new unit. See the examples below...
- Siege Striker is currently the unit with the strongest Attack power, at 400 against both buildings and units, obtainable from Atom Fusion. However it has a very low Speed and a very long attack Delay.
- You can't mix Spartan Warrior Mech and Red Mercury Dragon until you are at level 20.
- If you put spawns created by other units into Atom Fusion, it will fuse them normally but they will later disappear when you refresh or leave the game. Then you will get the "Atom Fusion glitch".
Powerup: You can try to enhance the fusion for a stronger unit by paying cash. The first powerup costs 1 cash, and subsequent powerups culminate to 2, 4, 8, 15 and 20 cash. It is NOT guaranteed that a powerup would result in a stronger unit. Sometimes it gives a weaker one instead (which is kind of ridiculous).
- This building is the Social Wars counterpart to the Soul Mixer in Social Empires, and the Breeding Mountain and Ultra Breeding Tree in Dragon City.
- With some monitors, you can find out what you are going to get before fusion by looking at your screen from a different angle, but only if you stare at the screen for a few seconds.