Warp Armor

You release a pulse of arcane energy that temporarily warps and weakens the armor of six creatures of your choice that are wearing armor in a 40-foot cube within range. Each target must succeed on a Constitution saving throw or be affected by this spell for the duration. Constructs and creatures wearing medium or heavy metal armor make this save with disadvantage.

An affected target takes a −2 penalty to Armor Class and attack rolls, and it makes Dexterity saving throws with disadvantage as the armor becomes awkward and unwieldy. 

A creature affected by this spell makes another Constitution saving throw at the end of each of its turns. On a successful save, the effect ends for it.

At Higher Levels. When you cast this spell using a spell slot of 4th level or higher, you can increase the penalty applied to the target's AC and attack rolls by 1 for each slot level above 3rd.