Brambles

A wooden or primarily wooden weapon you are wielding (such as a club or staff) grows thorns and barbs all over its surface. For the spell's duration, it deals an additional 2d4 piercing damage on hit.

At Higher Levels. When you cast this spell with a spell slot of 3rd or 4th level, the damage dice becomes a d6.

When you cast this spell with a spell slot of 5th or 6th level, the damage dice becomes a d8.

When you cast this spell with a spell slot of 7th level or higher, the damage dice becomes a d10.