Blade of Disaster

You create a 3-foot-long blade-shaped planar rift that lasts for the duration. The rift appears within range in a space of your choice, and you can immediately make up to two melee spell attacks, each one against a creature or object within 5 feet of the rift. On a hit, the target takes 10d6 Force damage. This attack scores a Critical Hit if the number on the d20 is 18 or higher. As a Bonus Action on your later turns, you can move the rift up to 60 feet and repeat the two attacks against a creature or an object within 5 feet of it. You can direct the attacks at the same target or at different ones. The blade can harmlessly pass through any barrier, including ones created by spells like Wall of Force.