Aetherspark/Persistent Marshstalker targeting
Similar to other reports re: Aetherspark avle to be targeted while attached, but this also includes creatures returning from the graveyard such as Persistent Marshstalker

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Rezzahan#77802 commented
Nothing about The Aeherspark makes it exempt from being targeted, attached or not, by anything that can target a legendary/artifact/equipment/planeswalker.
And while it cannot be attacked when attached to a creature, that only applies to attacker DECLARATION. Creatures entering attacking are attacking, but did not attack, were never declared as attackers, so they can get past The Aetherspark's "no attacking" clause. This is the same as with The Eternal Wanderer, where only one creature can attack her, but any creatures entering attacking can also be directed towards her. Same reason.