Chandra, Furia delle Fiamme

Chandra's last ability targets the player, not their creatures. A creature with hexproof may be dealt damage this way.

If the target creature is an illegal target by the time Chandra's second ability resolves, the ability doesn't resolve. No player is dealt damage. Similarly, if the target player is an illegal target by the time Chandra's last ability resolves, no creatures are dealt damage.