PoC vs Yubel TI

[squid]

greetings, miserables (don't forget the French accent). Its been forever since I've been online here, but Im facing a couple of deckbuilding questions and need a rule before I make my decisions.


Phantom of Chaos removes Yubel-Terror Incarnate from the Graveyard and copies its effect. During the End Phase, PoC stops copying and the "Yubel-TI" is no longer on the Field. Has the opportunity passed for that effect to trigger which summons the Yubel-Ultimate Nightmare?

This same scenario for PoC vs Doom Shaman: since Shaman is continuously targetting the Special Summoned monster and that targetting ceases when PoC stops 'being" Shaman, would the Summoned monster still be destroyed?


Last question is a separate matter:
Can I Tribute Ido the Supreme Magical Being for a Tribute Summon, since the act of Tributing happens as a cost, before the actual Summon?

 

[Entropy]

Phantom of Chaos removes Yubel-Terror Incarnate from the Graveyard and copies its effect. During the End Phase, PoC stops copying and the "Yubel-TI" is no longer on the Field. Has the opportunity passed for that effect to trigger which summons the Yubel-Ultimate Nightmare?

During the End Phase, you choose which to perform first. You can activate the effect from "Yubel - Terror Incarnate" and destroy all other monsters, and then resolve the effect of "Phantom of Chaos" and have him stop being treated as "Yubel - Terror Incarnate". Or, you can resolve the effect from "Phantom of Chaos" and have him stop being treated as "Yubel - Terror Incarnate", and then you can't activate the effect of "Yubel - Terror Incarnate" because "Phantom of Chaos" no longer has that effect.

This same scenario for PoC vs Doom Shaman: since Shaman is continuously targetting the Special Summoned monster and that targetting ceases when PoC stops 'being" Shaman, would the Summoned monster still be destroyed?

No. "Phantom of Chaos"/"Doom Shaman" was never removed from the field.

Last question is a separate matter:
Can I Tribute Ido the Supreme Magical Being for a Tribute Summon, since the act of Tributing happens as a cost, before the actual Summon?

No. The effect of "Ido the Supreme Magical Being" prevents you from even starting a Summon, so you can't start a Summon by Tributing him.