Time Link of Kai-El

As you cast this spell, a portal appears. Through it players can see you, a future you. You borrow an action from the next round of combat to cast a time based breath weapon as a bonus action. Each creature or object in a 30 ft line starting from you must make a dexterity saving throw. On a failed save they take 4d6 damage of your choosing and half as much damage on a success. The damage increases by 1d6 for every level cast above 2nd level. In the next round of combat you must forfeit your action regardless of time between rounds of combat or short/long rests.