Take the initiative

During the first round of combat on your turn you may gain a number of additional bonus actions equal to your dexterity modifier

These actions allow your character to utilize class specific features more times than normal. (such as sneak attack, or casting spells that only require a bonus action)

Using this ability completely drain your stamina, you gain 1 level of exhaustion for each addition bonus action you take. You may not use this feature while suffering for any of the following conditions; Blinded, Charmed, Frightened, Grappled, Incapacitated, Paralyzed, Petrified, Prone, Restrained, Stunned, Suprised, Unconscious, Exhaustion.