Black Hole (mega)

You bring your greatest arcane powers to bear and rip a hole in space itself, creating a black hole at a point in range. The black hole itself is incredibly small, but it affects all wildjammers and mega creatures within 1,500 feet of it. As soon as the black hole appears, all wildjammers or mega creatures are moved 500 feet closer to the black hole if possible. For the duration, any wildjammer or mega creature moving through this area must spend 4 feet of movement for every 1 foot it moves.
When a wildjammer or mega creature enters the area for the first time on a turn or starts its turn there, it must make a Constitution saving throw. On a failed save, the wildjammer or mega creature takes 10d6 + 40 mega force damage. On a successful save, the wildjammer or mega creatures takes half damage.