Brain in a Jar and last known information
If I control a Brain in a Jar with zero counters on it and activate its first ability, then while maintaining priority sacrifice it to Arcbound Ravager, am I able to cast a Hypergenesis (zero CMC sorcery) on resolution?
On the gatherer page you linked:
If Brain in a Jar leaves the battlefield before its first ability resolves, use the number of counters on it at the moment it left to determine what spell you may cast. That number won’t change because you can’t put a new counter on Brain in a Jar.
I found that ruling but was left unclear on its implications for 0 CMC spells without casting costs.
I dont think it work, because 0 CMC is not the same as "no CMC". When you cast a Mox (for example), you "pay 0", but the casting cost is still there. With suspend cards, there is no casting cost meaning you can't cast it.
Suspend ability say you pay N and exile the card. Then, at the beginning of your upkeep, suspend triggers letting you remove a suspend counter from the card, and when you remove the last counter, the suspend ability triggers again and say you may play the cards from the exile zone. But you still don't cast it, you "just play it".
@kravkenov This is incorrect. The CMC of any card without a mana cost is 0 - the most obvious example being lands. A nonexistent casting cost cannot be paid, but you can cast such a spell using an effect that lets you skip paying costs. The most common examples are casting Ancestral Vision or Living End off of a Cascade trigger.
Hmmm have to investigate how this works then ;)
@cutlex Yes, it works.