Multitasker

You have the ability. to hold up to two concentration spells at once. 

Each consecutive turn, you have to roll to see if you can maintain concentration on each spell. 

The DC is equal to the spell's level + your proficiency bonus. 

The save is equal to a d20 + your wisdom save modifier. 

This feat does not benefit from the advantage given by the "War Caster" feat, though the two feats can be had simultaneously. 

On a fail, you lose the spell of which you were not able to maintain concentration on.