Action Surge

You touch yourself or a creature within range, target creature gains 1 additional normal action on their next turn.

If the spell is casted at higher levels, the duration of the spell lasts an extra round per level. While the target creature has the spell casted on them, they cannot cast or have additional Surge spells active. In addition, if a creature casts Action Surge on another creature and the caster dies, the spell wears off. 

(Casted at level 1 gives 1 extra action next round. Casted at level 2 gives 1 extra action for the next 2 rounds. Casted at level 3 gives 1 extra action for the next 3 rounds, etc.)