This spell is available at Xanathar’s Guide to Everything
Casting Time: 1 action
Range: 90 feet
Components: V, S
Duration: Concentration, up to 1 minute
As per this spell you can select one creature that you can see within a range, and even select one of the following damage types such as: acid, cold, fire, lightning, or thunder. The target should be succeeded upon a Constitution saving throw or it should be affected by the specific spell for its duration.
However the first time each turn the affected target shall take the damage of any selected type, anyway the target shall take an extra 2d6 damage of that particular type. Moreover, the target shall lose any resistance to that damage type until the spell ends.
Also read: Control Flames 5e uses
At Higher Levels:
Whenever you cast this spell by using the spell slot of 5th level or else higher, you are able to target an additional creature for each slot level above 4th. Anyhow the creatures should be within 30 feet of each other when you shall target them.