Something unusual with battery life - S7 edge

[AC Question]

2hrs non-stop usage..mostly gaming..then battery drastically drops down to 40% from 100%

 

[Rukbat]

Check the battery in Settings. Tap the graph so you get the second one. Look for a sharp drop in voltage to 0 or nearly 0. If you see that around the time the voltage dropped, the battery is bad (it has a dendrite).