Acceleration Sphere

You channel your internal magic, causing time to disrupt around a point that you choose within range. A 15 foot radius sphere is created at the target location. The sphere is coated in a shell of energy that pulsates along the outside of it, but is other wise transparent.

Creatures that start their turn within the sphere, and until the start of their next turn, have their speed is doubled, gain a +2 bonus to AC, have advantage on Dexterity saving throws, and they gain an additional action on each of its turns. That action can be used only to take the Attack (one weapon attack only), Dash, Disengage, Hide, or Use an Object action.