Armageddon

You brandish the weapon used in the casting and make a melee spell attack against one target within 10 ft. +30 to hit, the target takes 50d6 radiant damage, 50d6 necrotic damage, and 50d6 force damage as a enormous shockwave of divine light and darkness bursts forth from the blade. The damage ignores resistances and immunities.

The effort from casting Armageddon leaves you weakened. After using Armageddon you may not use it again until 1d4 long rests have passed. In addition, your Strength score becomes 3 for 2d4 days. For each of those days that you spend resting and doing nothing more than light activity, your remaining recovery time decreases by 2 days.