If Rubinia Soulsinger stops being tapped before its ability resolves — even if it becomes tapped again right away — you won't gain control of the targeted creature at all. The same is true if you lose control of Rubinia Soulsinger before the ability resolves.
Once the ability resolves, it doesn't care whether the targeted permanent remains a legal target for the ability, only that it's on the battlefield. The effect will continue to apply to it even if it gains shroud, stops being a creature, or would no longer be a legal target for any other reason.
If Rubinia Soulsinger leaves the battlefield, you no longer control it, so the duration of its control-change effect ends.
This printing is one of 3 catalogued treatments from ME3 — the lineup includes Foil and Nonfoil alongside the standard finish. Across our catalog the Rarix library tracks every variant in the same family so collectors can compare price, scarcity and demand inside a single lineage.
Card #173 of *Masters Edition III*, the set that shipped alongside the September 2009 Masters Edition III release.
Card type: Legendary Creature — Faerie, color identity green/blue/white, printed at rare. Rares occupy the bottom-of-pack rare slot in standard boosters. Mana cost: {2}{G}{W}{U} (5 converted).
Legal in Legacy, Vintage, and Commander.
EDHrec ranks this card #18,405 in Commander, putting it in the fringe-play tier of the format's playable pool.
Illustrated by Rob Alexander. Rarix catalogs 951 other cards credited to this artist.
Magic: The Gathering · ™ & © Wizards of the Coast · Illus. Rob Alexander
Card data via Scryfall. Rarix is fan-made; not endorsed by the rights holders.
