Let's say that I or one of my opponents casts ghostly flicker to flicker two permanents.
I respond by casting dualcaster mage (When Dualcaster Mage enters the battlefield, copy target instant or sorcery spell. You may choose new targets for the copy) and copy the spell by flickering dualcaster mage and another permanents I control. When the mage returns, can it copy the ghostly flicker again? This would allow me to flicker lands (infinite mana), creatures (infinite ETB triggers), and artifacts.
You can target the spell with Dualcaster Mage and you get the copy above the spell you responded to (Ghostly Flicker).
The copy resolves and that flickers dualcaster mage and another target, which will have dualcaster mage enter the battlefield trigger again and you just repeat.
To "end" the loop you have to not flicker the dualcaster mage, as its ability is not optional (you still need a target for it, but if you have a target, its must copy the spell).
Yes, the same logic applies to Rite of Replication. You (or someone) casts the Rite targeting something, and you respond with Dualcaster Mage, with it's ETB ability targeting Rite. If it's not kicked, you can just get an army of bears and one copy of something else. If it is kicked, then you can get 5 additional Dualcaster Mages for each Rite you target (and potentially copies of other things as well).
And if I cast rite of replication on it, that will be infinite mages too, correct?
That depends what you mean. If you respond to a Rite by casting the Mage, and copy the Rite that way, it'll work (since the triggers of the token copy/ies of the Mage can copy the original).
However, you won't be able to copy the Rite if you cast the original one targeting the Mage (that's how I interpreted "cast rite of replication on it [the Mage]"), since in that case the original will have already finished resolving by the time you choose the target for the Mage's trigger.
I respond by casting dualcaster mage (When Dualcaster Mage enters the battlefield, copy target instant or sorcery spell. You may choose new targets for the copy) and copy the spell by flickering dualcaster mage and another permanents I control. When the mage returns, can it copy the ghostly flicker again? This would allow me to flicker lands (infinite mana), creatures (infinite ETB triggers), and artifacts.
My G Yisan, the Bard of Death G deck.
My BUGWR Hermit druid BUGWR deck.
You can target the spell with Dualcaster Mage and you get the copy above the spell you responded to (Ghostly Flicker).
The copy resolves and that flickers dualcaster mage and another target, which will have dualcaster mage enter the battlefield trigger again and you just repeat.
To "end" the loop you have to not flicker the dualcaster mage, as its ability is not optional (you still need a target for it, but if you have a target, its must copy the spell).
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And if I cast rite of replication on it, that will be infinite mages too, correct?
That dualcaster mage is amazing. I want dozens of them.
My G Yisan, the Bard of Death G deck.
My BUGWR Hermit druid BUGWR deck.
Draft my cube! (630 cards)
That depends what you mean. If you respond to a Rite by casting the Mage, and copy the Rite that way, it'll work (since the triggers of the token copy/ies of the Mage can copy the original).
However, you won't be able to copy the Rite if you cast the original one targeting the Mage (that's how I interpreted "cast rite of replication on it [the Mage]"), since in that case the original will have already finished resolving by the time you choose the target for the Mage's trigger.
My G Yisan, the Bard of Death G deck.
My BUGWR Hermit druid BUGWR deck.