The text specifies 7d8 damage and yet the tool tip and die roller specifies 7d6:
You conjure two 10ft by 10ft stone walls with 10 feet between them. They then smash together, attempting to crush whatever is between them. Any creatures that are completely within the area crushed by the walls must make a strength saving throw against your spell save DC. On a failure the creature takes 7d8 bludgeoning damage and have their speed reduced to 0 until the end of their turn, on a success they take half as much damage and their speed is unaltered.
The text specifies 7d8 damage and yet the tool tip and die roller specifies 7d6:
You conjure two 10ft by 10ft stone walls with 10 feet between them. They then smash together, attempting to crush whatever is between them. Any creatures that are completely within the area crushed by the walls must make a strength saving throw against your spell save DC. On a failure the creature takes 7d8 bludgeoning damage and have their speed reduced to 0 until the end of their turn, on a success they take half as much damage and their speed is unaltered.
Versus
Cast Level 4th 7d6 Damage
There is no official spell by that name. It must be homebrew, and only the creator can fix it.
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