Runic Armasaur's ability doesn't trigger when an opponent activates an ability of a card in hand (such as a cycling ability from the Amonkhet block) or a card in a graveyard (such as that of Bone Dragon), even if that causes a card to be put onto the battlefield.
Activated abilities contain a colon. They're generally written "[Cost]: [Effect]." Some keyword abilities are activated abilities and will have colons in their reminder text. An activated mana ability is one that produces mana as it resolves, not one that costs mana to activate.
Runic Armasaur's ability resolves before the ability that caused it to trigger. Players can cast spells and activate abilities after the triggered ability resolves but before the activated ability that caused it to trigger does.
Last observed on Scryfall 2 months ago at $6.33. Over the trailing 90 days the price moved between $3.24 and $6.33 across 45 observations. Cross-checked across TCGplayer, eBay sold, Cardmarket EU, and Star City.
This printing is one of 3 catalogued treatments from PM19 — 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 #200p of *Core Set 2019 Promos*, the promotional run that shipped alongside the July 2018 Core Set 2019 release.
Card type: Creature — Dinosaur, color identity green, printed at rare. Rares occupy the bottom-of-pack rare slot in standard boosters. Mana cost: {1}{G}{G} (3 converted).
Legal across the major constructed formats — Modern, Legacy, Vintage, and Commander — plus Standard rotation play.
EDHrec ranks this card #2,350 in Commander, putting it in the niche-pick tier of the format's playable pool.
Illustrated by Randy Vargas. Rarix catalogs 627 other cards credited to this artist.
Magic: The Gathering · ™ & © Wizards of the Coast · Illus. Randy Vargas
Card data via Scryfall. Rarix is fan-made; not endorsed by the rights holders.
Runic Armasaur's ability doesn't trigger when an opponent activates an ability of a noncreature, nonland permanent that causes it to become a creature (such as a crew ability of a Vehicle).
