Suspended Cards

[The_Red_Panda]

Do I have to cast a suspended card when the last counter is removed? For instance, if I'm playing Sek'Kuar EDH, and I have Greater Gargadon suspended, can I simply not cast him when the last counter is removed, and then have the ability to freely sacrifice creatures at any time?, or must I cast the Gargadon when the last time counter is removed?

Also, how would this work if my opponent has Teferi in play? If I remove the last time counter from Greater Gargadon, and yet cannot cast him, can I continue to sacrifice creatures to remove time counters from him? Will I be forced to cast him the first time I have a chance?

[DownSyndromeKarl]

does it say "may"?

no.

[luma]

When the last time counter is removed, you have to cast the card if you can. If your opponent has Teferi on the battlefield, you can't cast the card. The card will stay exiled, and you can't cast it anymore because suspend's "cast me" ability triggers only once, when the last time counter is removed from the card.

If a Greater Gargadon is left in exile because of Teferi or something else, you can't sacrifice things to it anymore. The activated ability has a restriction: "Activate this ability only if Greater Gargadon is suspended." A card is "suspended" if it's in the exile zone, has suspend, and has a time counter on it (rule 702.59b). Because Gargadon doesn't have any time counters on it, it's not "suspended" and you can't activate the ability.