If my opponent and I both control a SotPC and I also control a Ranar, then a fetch land is exiled, whose replacement effect is it? (i.e., if my Ranar can trigger)
I assume you mean "is exiled rather than sacrificed" rather than just "is exiled".
That's a decision for whoever controls the permanent that would go to the graveyard. Here, there are two replacement effects that would affect where the permanent would go, so that permanent's controller chooses which effect to apply (C.R. 616.1). Thus, for example, if the permanent that would go to the graveyard is controlled—
by your opponent, they can choose to apply the Samurai of the Pale Curtain they control so that they exile the permanent instead, rather than you; if they exile the permanent this way, Ranar's last ability won't trigger for that permanent.
by you, you can choose to apply the Samurai of the Pale Curtain you control so that you exile the permanent and so satisfy Ranar's last ability.
by a player other than you or your opponent, that player chooses which replacement effect to apply (and so decide who exiles the permanent in this case).
Note that Samurai of the Pale Curtain's second ability applies to any permanent (not just lands like Windswept Heath) that would go to any graveyard by any means (not just by sacrificing). It doesn't apply if a permanent would be exiled directly (such as by Swords to Plowshares or Banishing Light).
With the release of Strixhaven: School of Mages, the Oracle text of Ranar changed in a manner that materially affects this question.
Specifically, on Ranar's last ability, the text "Whenever you exile..." was changed to "Whenever a spell or ability you control exiles...".
However, this text change made the behavior of Ranar unclear in the face of replacement effects that exile permanents, such as with Rest in Peace, as well as static abilities such as madness (C.R. 702.34a). This is especially since at the time of this writing, the only abilities that the comprehensive rules speak of as having a controller are activated and triggered abilities on the stackactivated abilities on the stack, mana abilities, and triggered abilities on the stack or waiting to go on the stack (C.R. 113.8; see also C.R. 109.4C.R. 109.4, especially C.R. 109.4a-b), not static abilities such as Rest in Peace's second ability (C.R. 113.3d; compare C.R. 113.1c with C.R. 113.1).
And unfortunately, the update bulletin for Strixhaven: School of Mages didn't point out this Oracle text change in Ranar, and neither did the update to the rules add clarification on whether foretell (C.R. 702.142a), madness (C.R. 702.34a), Rest in Peace's second ability, or other static abilities have controllers for purposes of Ranar's triggered ability. (Indeed, the bulletin went over Elemental Expressionist, where "When you exile this creature..." was changed to "When this creature is put into exile...", although for different reasons than the case of Ranar.)
With the release of Modern Horizons 2, the Oracle text of Ranar's triggered ability changed again. Now, the ability reads in part, "Whenever one or more cards are put into exile from your hand or a spell or ability you control exiles one or more permanents from the battlefield, ..."
With this change, for example, the ability will trigger when one or more cards are exiled from "your hand" by any means, including—
due to foretell (C.R. 702.143a), suspend (C.R. 702.62a), or madness (C.R. 702.35a),
when Rest in Peace (controlled by any player) exiles a card "you discard" that would otherwise go to the graveyard.
However, the new text change retains the behavior from the previous text change with respect to permanents. In particular, if we follow the logic of the rulings for Firesong and Sunspeaker, it would follow that for purposes of Ranar, a spell or ability "exiles [a] ... permanen[t] from the battlefield" "if its cost or effect instructs [a permanent to be exiled] or if an instruction in its cost or effect is modified by a replacement effect and the modified event includes [a permanent being exiled]".
Thus, under the current Oracle text of Ranar:
Ranar's triggered ability generally will trigger if you control Ranar and—
you would discard one or more cards by any means (including by a spell or ability you don't control), but those cards are exiled instead of going to the graveyard (e.g., because someone controls Rest in Peace).
one or more cards are exiled from your hand by any means (including by a spell or ability you don't control such as Kitesail Freebooter's enters-the-battlefield ability).
one or more permanents (even permanents you don't control) would be destroyed or sacrificed while a spell or ability you control is resolving, but those permanents are exiled instead of going to the graveyard (e.g., because someone controls Rest in Peace).
one or more permanents (even permanents you don't control) are exiled while a spell or ability you control (such as Swords to Plowshares or Path to Exile) is resolving.
On the other hand, Ranar's triggered ability generally won't trigger if you control Ranar and a permanent is exiled—
while a spell or ability you don't control is resolving, or
even if you controlled that permanent and even if the permanent is exiled rather than going to a graveyard.
The second point covers in particular the case when a creature is destroyed as a state-based action due to lethal damage (C.R. 704.5g), but is exiled rather than going to the graveyard, e.g., because someone controls Rest in Peace.
The third point, however, is arguably in conflict with a ruling for Firesong and Sunspeaker, where for purposes of that card, a spell "causes you to gain life if [among other things] its cost or effect instructs you to gain life or if an instruction in its cost or effect is modified by a replacement effect and the modified event includes you gaining life". If costs are not similarly included in the meaning of "a spell or ability ... exiles [a] ... permanen[t] from the battlefield", then that would be an apparent inconsistency that—
is not otherwise resolved by the comprehensive rules, and
has yet to be resolved or explained by the rules manager.
EDIT (Jun. 28, Jul. 19): Edited.
EDIT (Jul. 31): Edited to account for a statement by the rules manager.
If my opponent and I both control a SotPC and I also control a Ranar, then a fetch land is exiled, whose replacement effect is it? (i.e., if my Ranar can trigger)
Shu Yun, the Silent Tempest WUR Voltron Control
Temmet, Vizier of Naktamun WU Unblockable Mirror Trickery
Ra's al Ghul (Sidar Kondo) and Face-Down Ninjas
Brudiclad, Token Engineer
Vaevictis (VV2) the Dire Lantern
Rona, Disciple of Gix
Tiana the Auror
Hallar
Ulrich the Politician
Zur the Rebel
Scorpion, Locust, Scarab, Egyptian Gods
O-Kagachi, Mathas, Mairsil
"Non-Tribal" Tribal Generals, Eggs
That's a decision for whoever controls the permanent that would go to the graveyard. Here, there are two replacement effects that would affect where the permanent would go, so that permanent's controller chooses which effect to apply (C.R. 616.1). Thus, for example, if the permanent that would go to the graveyard is controlled—
; if they exile the permanent this way, Ranar's last ability won't trigger for that permanent.and so satisfy Ranar's last ability.See also this thread.
Note that Samurai of the Pale Curtain's second ability applies to any permanent (not just lands like Windswept Heath) that would go to any graveyard by any means (not just by sacrificing). It doesn't apply if a permanent would be exiled directly (such as by Swords to Plowshares or Banishing Light).
EDIT (Apr. 22): See comment 4.
Shu Yun, the Silent Tempest WUR Voltron Control
Temmet, Vizier of Naktamun WU Unblockable Mirror Trickery
Ra's al Ghul (Sidar Kondo) and Face-Down Ninjas
Brudiclad, Token Engineer
Vaevictis (VV2) the Dire Lantern
Rona, Disciple of Gix
Tiana the Auror
Hallar
Ulrich the Politician
Zur the Rebel
Scorpion, Locust, Scarab, Egyptian Gods
O-Kagachi, Mathas, Mairsil
"Non-Tribal" Tribal Generals, Eggs
Specifically, on Ranar's last ability, the text "Whenever you exile..." was changed to "Whenever a spell or ability you control exiles...".
However, this text change made the behavior of Ranar unclear in the face of replacement effects that exile permanents, such as with Rest in Peace, as well as static abilities such as madness (C.R. 702.34a). This is especially sinceat the time of this writing, the only abilities that the comprehensive rules speak of as having a controller areactivated and triggered abilities on the stackactivated abilities on the stack, mana abilities, and triggered abilities on the stack or waiting to go on the stack (C.R. 113.8;see also C.R. 109.4C.R. 109.4, especially C.R. 109.4a-b), not static abilities such as Rest in Peace's second ability (C.R. 113.3d; compare C.R. 113.1c with C.R. 113.1).And unfortunately, the update bulletin for Strixhaven: School of Mages didn't point out this Oracle text change in Ranar, and neither did the update to the rules add clarification on whether foretell (C.R. 702.142a), madness (C.R. 702.34a), Rest in Peace's second ability, or other static abilities have controllers for purposes of Ranar's triggered ability. (Indeed, the bulletin went over Elemental Expressionist, where "When you exile this creature..." was changed to "When this creature is put into exile...", although for different reasons than the case of Ranar.)
I have notified the new rules manager, and fortunately his response acknowledges that the "wording was updated in a way that makes that unclear".
EDIT (Jun. 19): Edited.
Shu Yun, the Silent Tempest WUR Voltron Control
Temmet, Vizier of Naktamun WU Unblockable Mirror Trickery
Ra's al Ghul (Sidar Kondo) and Face-Down Ninjas
Brudiclad, Token Engineer
Vaevictis (VV2) the Dire Lantern
Rona, Disciple of Gix
Tiana the Auror
Hallar
Ulrich the Politician
Zur the Rebel
Scorpion, Locust, Scarab, Egyptian Gods
O-Kagachi, Mathas, Mairsil
"Non-Tribal" Tribal Generals, Eggs
With this change, for example, the ability will trigger when one or more cards are exiled from "your hand" by any means, including—
In particular, if we follow the logic of the rulings for Firesong and Sunspeaker, it would follow that for purposes of Ranar, a spell or ability "exiles [a] ... permanen[t] from the battlefield" "if its cost or effect instructs [a permanent to be exiled] or if an instruction in its cost or effect is modified by a replacement effect and the modified event includes [a permanent being exiled]".Thus, under the current Oracle text of Ranar:
Ranar's triggered ability generally will trigger if you control Ranar and—
On the other hand, Ranar's triggered ability generally won't trigger if you control Ranar and a permanent is exiled—
The second point covers in particular the case when a creature is destroyed as a state-based action due to lethal damage (C.R. 704.5g), but is exiled rather than going to the graveyard, e.g., because someone controls Rest in Peace.
The third point, however, is arguably in conflict with a ruling for Firesong and Sunspeaker, where for purposes of that card, a spell "causes you to gain life if [among other things] its cost or effect instructs you to gain life or if an instruction in its cost or effect is modified by a replacement effect and the modified event includes you gaining life". If costs are not similarly included in the meaning of "a spell or ability ... exiles [a] ... permanen[t] from the battlefield", then that would be an apparent inconsistency that—
EDIT (Jun. 28, Jul. 19): Edited.
EDIT (Jul. 31): Edited to account for a statement by the rules manager.