Formidable Guarding

Whenever you choose to withstand an area effect by simply standing against it, you can also protect those around you. If you succeed on your Constitution saving throw against an area effect, you can choose a number of creatures equal to your size modifier, none bigger than your size, and who chose the Dexterity saving throw to evade this effect, to take cover behind you. Creatures who take cover behind you this way take no damage when they succeed on their Dexterity saving throw against that area effect, and take half as much damage if they fail. The size modifiers for each type are as follows:
Tiny: 0
Small: 1
Medium: 2
Large: 4
Huge: 8
Gargantuan: 16