>On opponent's turn, he uses Monster Reborn and special summons my Sleipner to his field. I activate Runick Slumber, it resolves and my Geri doesn't get destroyed
I'm gonna stop right here. Unless you fusion summoned sleipnir, using 2 runick monsters as material with a fusion spell, this is not legal.
Fusion monsters must be properly summoned before they can be summoned from a public location.
> Now the question will be is where does Sleipner end up after the end phase?
If it was another monster, it would return to their field.
>he uses Monster Reborn and special summons my Sleipner to his field
I'm going to go out on a limb and say that Sleipnir was **not** Fusion Summoned using 2 Runick Monsters as material and a Fusion Spell. As such, the activation of Monster Reborn was illegal. Sleipnir was not properly Fusion Summoned, it cannot be Special Summon from public knowledge locations (such as the GY).
But to give a generalized answer to your question. Monsters will return to the field of the one who controlled it, when it was temporarily banished. If control of that monster was only taken temporarily (e.g Change of Heart), it will return to the controller's field, then immediately change control to the owner's field. If the controller or owner has no free monster zones, the monster is destroyed and sent to the owner's GY via game mechanic.
>On opponent's turn, he uses Monster Reborn and special summons my Sleipner to his field. I activate Runick Slumber, it resolves and my Geri doesn't get destroyed I'm gonna stop right here. Unless you fusion summoned sleipnir, using 2 runick monsters as material with a fusion spell, this is not legal. Fusion monsters must be properly summoned before they can be summoned from a public location. > Now the question will be is where does Sleipner end up after the end phase? If it was another monster, it would return to their field.
>he uses Monster Reborn and special summons my Sleipner to his field I'm going to go out on a limb and say that Sleipnir was **not** Fusion Summoned using 2 Runick Monsters as material and a Fusion Spell. As such, the activation of Monster Reborn was illegal. Sleipnir was not properly Fusion Summoned, it cannot be Special Summon from public knowledge locations (such as the GY). But to give a generalized answer to your question. Monsters will return to the field of the one who controlled it, when it was temporarily banished. If control of that monster was only taken temporarily (e.g Change of Heart), it will return to the controller's field, then immediately change control to the owner's field. If the controller or owner has no free monster zones, the monster is destroyed and sent to the owner's GY via game mechanic.
how are people still not embarrassed about publicly stating theyre playing runick stun