15 cards where it’s legal in Standard and the text includes “indestructible” and the card types include “instant”

Battle-Rage Blessing (Dominaria United #80)
Crumb and Get It (Bloomburrow #8)
Dawn's Truce (Bloomburrow #9)
Final Showdown (Outlaws of Thunder Junction #11)
Gaea's Gift (The Brothers' War #182)
Loran's Escape (The Brothers' War #14)
Moment of Valor (Wilds of Eldraine #20)
Offer Immortality (Phyrexia: All Will Be One #102)
Overprotect (Bloomburrow #185)
Rebel Salvo (Phyrexia: All Will Be One #144)
Resistance Reunited (Phyrexia: All Will Be One #31)
Scales of Shale (Bloomburrow #110)
Smuggler's Surprise (Outlaws of Thunder Junction #180)
Take Up the Shield (Outlaws of Thunder Junction #34)
Tyvar's Stand (Phyrexia: All Will Be One #190)

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