Tactical equipment is one of the three items in your loadout. You have two guns and a tactical item of sorts. This could be a highly damaging weapon, or it could stun or immobilize them so you can get away in times of dire straights.
To use your tactical equipment, you must first fill up the circular gauge below your equipped weapons ammo counter. This is in the bottle right-hand corner of the screen. The circular gauge starts to fill up upon dealing damage to enemies.
Once this is full, it'll turn red and start flashing. This means that it can be used. Next, all you have to do is press Left Thumbstick in on controller or G on keyboard, and the tactical item will be used.
Depending on the item you have equipped, you can choose to detonate the item early if groups of enemies are clustered together from the get-go. If your tactical loadout is a drone, then it'll be on a set time duration, which will disappear once its time limit has been reached.
Upon use, the gauge will be completely emptied but can be refilled by once again dealing damage to enemies. No matter what item you have selected in your tactical loadout, they are all used the same way. The only difference is that some tactical items have a shorter/longer charging gauge than others, so it requires less/more filling to use.
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