Frontline Medic
Creature — Human Cleric
Battalion — Whenever this creature and at least two other creatures attack, creatures you control gain indestructible until end of turn.
Sacrifice this creature: Counter target spell with 
in its mana cost unless its controller pays 
.
"The world is full enough of hurts and mischances without wars to multiply them."
Francesca Resta
Rulings
The three attacking creatures don't have to be attacking the same player, planeswalker, or battle.
(wotc • 2024-01-12)
Creatures that come under your control after Frontline Medic's battalion ability resolves will not be granted indestructible by this effect.
(wotc • 2013-07-01)
Once a battalion ability has triggered, it doesn't matter how many creatures are still attacking when that ability resolves.
(wotc • 2013-04-15)
The effects of battalion abilities vary from card to card. Read each card carefully.
(wotc • 2013-04-15)
Rulings
The three attacking creatures don't have to be attacking the same player, planeswalker, or battle.
(wotc • 2024-01-12)
Creatures that come under your control after Frontline Medic's battalion ability resolves will not be granted indestructible by this effect.
(wotc • 2013-07-01)
Once a battalion ability has triggered, it doesn't matter how many creatures are still attacking when that ability resolves.
(wotc • 2013-04-15)
The effects of battalion abilities vary from card to card. Read each card carefully.
(wotc • 2013-04-15)