On your journey through The Ascent, you'll come across many side missions. One, in particular, is a mission you get very early in the game, called Double Charge. Take note that the recommended level to complete this quest is level 7.
To complete this quest, you need to make 10 Overcharge kills. Overcharge occurs in The Ascent that happens when you deal enough damage to an enemy under Stasis's effect. Stasis is a state which will halt their movements and cause them to take additional damage. If that damage exceeds their max health, they'll Overcharge and explode.
The stasis effect can only be caused by certain augmentations or tactical equipment. The fastest way to get a piece of equipment that does this is the Stasis Drone, from the Cyber Vendor in Cluster 13, for 22,000 Ucred. It's a hefty price tag, but by level 7, you should have enough money saved up.
Equip the Stasis Drone in your tactical slot under Loadout, then wait till the tactical gauge charges up in combat by killing foes. Once it's full, press Left Thumbstick or G, and it'll use your tactical equipment. The Stasis Drone will fly to specific locations near your location and create an area of effect circle where it fires at single enemies and puts them under stasis.
You have to then shoot the person under stasis. If done correctly, they'll grow in size and then explode, killing them. This must be done 10 times you complete the quest. The drone will only hit two people each use, so it will take a while to get all 10 kills.
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