Railgunner: Trickshot

 is a challenge in Risk of Rain 2, added in the Survivors of the Void expansion. It is completed as by killing 3 enemies with a single  shot while Airborne.

Completing it unlocks the in Railgunner's loadout.

Tips

 * Letting weak enemies like or  group up is very effective, and can allow you to complete the challenge as early as Stage 1.
 * Having more than 3 enemies group up gives a greater chance of killing as many as you need.
 * takes about half a second to fire once triggered, keep that in mind if you're only jumping to go airborne.