How did/does The Immortal Sun/Guildpact/Elesh Norn & Memnarch’s spells work in regards to anti-planeswalking? Like, does it disrupt the aether so planeswalkers can’t focus enough to travel? Or is it more like a balloon barrier around the plane?Oooh, it’s been a while since I had a fun metaphysics question.
The Immortal Sun detects planeswalking and creates a magical barrier to prevent it through Azor’s hieromancy. More than likely it’s an enchantment covering the whole plane that just activates or is visible when someone planeswalks (hence the sigil).
The Guildpact is only implied to prevent planeswalking (namely, that planeswalkers stopped showing up after a while) and along with it creating the pocket plane of Agyrem, it’s implied that it just warped the metaphysics around itself to cut itself off. This was common in older lore, as similar things happened with the Shard of Twelve Worlds (a barrier that cut twelve planes off from the rest of the multiverse after the Sylex Blast) and Shandalar between the end of the video game and its return in Magic 2013ish. Planar barriers weren’t unusual in lore, and the metaphysics wasn’t really ever explained outside of planeswalkers simply being unable to get past it.
Memnarch sort-of unconsciously prevented Karn from re-entering the plane because of the Mirari’s reality warping abilities. At least that’s how I assume it happened, it’s mostly off-handedly mentioned that Karn wasn’t able to return without much of an explanation.
The barrier on New Phyrexia wasn’t really a barrier, more like a ‘diffuser’ that made planeswalking to a specific location impossible.
