Exkalor's Plasmatic Cube

While you hold the crystal dice a bright blue light flashes from your hand and a cubic area (the cube's length equle to half your spellcasting modifer times 5 ft.) with in 100 ft. start glowing in a Blue light. Each in creature in the erea must make a Dexterity saving throw saving throw. on a successful save they have to use their bonus action to move out of the cube's range. In your next turn each creature in the cube must choose one of the cube's sides, in your next turn you can drop the dice in the air the dice will magicly float and start spinning roll a d6 the dice would then stop and in air and start shining while the cube would start rolling in any direction (DM's coise) and stop on a number each creature in the cube must take the number you roll on your d6 times your spellcasting modifier (Radiant Damage) but if the cube is landing on the side they choose the magicly teleported outside the cube. this could happen again and again until the cube is destroyed or until the cube landed on each of it's sides at least once

Destroying the cube: the cube can't be attacked from inside but can be attacked from outside it has a armor class of 10 + your spellcasting modifer and hit point equle to the side that it currently landing on times 20 (20-120 hit points) all of it's hit point is reseted in the start of your turn. Aditionally killing you make the cube disappear but dispel magic and counterspell won't effect it.

at higher levels  When you cast this spell using a 7th level spell slots the 6 sided dice turns into a 8 sided dice and when you cast this spell using a 9th level spell slots the 6 sided dice turns into a 10 sided dice