Tasha's Arc of Plasma

An arc of plasma emanates from you in a line 30 feet long and 5 feet wide in a direction you choose. A creature must make a dexterity saving throw or be ensnared by the arc and take 2d4 lightning damage. Each creature in the line that is wearing metal armor takes double damage. Another creature may spend an action to pull an affected creature out of the arc. The affected creature stops taking damage either when it passes a dexterity saving throw or the spell ends

At Higher Levels. When you cast this spell using a spell slot of 2nd level or higher, the damage increases by 2d4 for each slot level above 1st.