Overdrive

*chuckles*  "You're in danger."

You have learned how to briefly override your safety limits and force your power output to surge. As a bonus action, you can cast Haste (range: Self). When the spell ends, you gain a point of exhaustion. The normal rules for concentration checks apply even if you are not a spellcaster.

Additionally, when you take lightning damage, you may make a Constitution check. The DC for this check is (20 — the amount of lightning damage taken). If the lightning damage total is more than 20, you automatically succeed. On a success, you may cast Haste as a bonus action without suffering a point of exhaustion.