Syrvayas' Dome of Temporal Morass

You create a 30-foot-radius sphere of warped time centered on you. The sounds of a clock ticking and sand pouring through an hourglass eminates while inside the sphere. When a hostile creature starts its turn within the radius of the sphere, they must make a Constitution saving throw. On a failed save, the creature has its movement speed reduced by half, and it must choose whether it gets a move, an action, or a bonus action; it gets only one of the three. Whenever a friendly creature starts its turn within the radius of the sphere, its movement speed is doubled, and it can make an additional Action this turn, even if it leaves the radius of the sphere. The spell ends if you use your action to do anything else besides maintain concentration.