Young Viserion, the Proud

Flying
{r}: This creature gets +1/+0 until end of turn.
At the beginning of your end step, if you control
creatures named Young Drogon, the Strong and
Young Rhaegal, the Wise, then Young Viserion,
the Proud gains hexproof until your next end
step.
Viserys was cruel and weak and frightened, yet he was
my brother still, His dragon will do what he could not.