Tyroh's Giant Shield

When you are targeted by a harmful physical effect (Such as a blue dragon's lightning breath, a volley of arrows, or a fireball spell) you summon a large circular shield of force. 30 feet radius. The barrier is a shimmering transparent field. A creature fully covered by the barrier has full cover from physical effects. 
The barrier is indestructible until the start of your next turn. On your next turn you can choose to maintain the barrier, using your action. From that point on it counts as concentration. The barrier then has an HP equal to 10 times the spell level. An AC equal to 8 + the spell's level + your spellcasting modifier. Immunity against psychic and poison damage, and resistance against force damage. At the start of each of your turns it heals 5 x your spellcasting modifier

If an ally within 15 feet of you is targeted by a similar physical effect. You can move up to 15 feet and put the barrier up in front of both of you