does this work

[AdamS]

{Vish Kal, Blood Arbiter}+{It That Betrays}+{Grave Pact}+{Mikaeus, the Unhallowed}

ok so having all 4 cards plus any other crature to sac to vish then you steal opponents creature and sac the opponents creature to vish. so because of undying the opponent gets it back with a +1/+1 counter on it.
if this is right then when you sac the creature you stole then it is given back to the opponent and you get a new creature from them and then you sac the new one and repeat.
so is this an infinite combo or am i miss reading something

[Sardok]

When a non-human creature you control dies with undying, it will come into play under your control with a +1/+1 counter on it. This is true even for creatures you control but do not own, for example creatures stolen with {It That Betrays}.

This combo will work until your opponent runs out of creatures.

[abstractApathist]

It works to make Vish Kal infinitely large Here's what it looks like:

1. Sac a creature to {Vish Kal, Blood Arbiter}
2. Your opponent sacs a creature to {Grave Pact}
3. You get your creature back with a +1/+1 counter because of {Mikaeus the Unhallowed}
4. You get their creature that they sacrificed because of {It that Betrays}
5. Sac their creature to Vish Kal and they get it back from undying
6. They sac the undying creature and you get it because of {It that Betrays}
7: Repeat steps 5&6 infinitely

[abstractApathist]

When a non-human creature you control dies with undying, it will come into play under your control with a +1/+1 counter on it. This is true even for creatures you control but do not own, for example creatures stolen with {It That Betrays}.

This combo will work until your opponent runs out of creatures.

It comes into play under its owner's control.

702.92a: Undying is a triggered ability. "Undying" means "When this permanent is put into a graveyard from the battlefield, if it had no +1/+1 counters on it, return it to the battlefield under its owner's control with a +1/+1 counter on it."

[AdamS]

making vish linfite was what i was going for

[Sardok]

Wow, I really need to RTFC.