Last hope of the Underground

Put two hope counters on target creature, that creature gains undying X until end of turn. if
that creature dies this turn, when is returned
to the battefield, put four hope counters on it.

"No... My body... It feels like it's splitting apart.
Like any instant... I'll scatter into a million pieces.
But... Deep, deep in my soul. There's
a burning feeling i can't describe. A burning feel that...
WON'T let me die!"
—Undyne, the Undying