Elemental Surge

You touch a willing creature within range. Any weapon they are holding is imbued with elemental energy. Choose one damage type from fire, lightning, cold, acid, or poison. For the duration, the target's weapon attacks deal an additional 1d4 damage of this type, and the target's weapon counts as magical.

At higher level

When you cast this spell using a spell slot of 3rd, 5th, 7th, and 9th level, the damage increases by 1d4 for every incremental slot level above 1st.