Yisan + Genesis hydra

[RDJDenley]

... If I were to 'cast' genesis hydra from a yisan activation, how would that work exactly?

[blackychan1]

It would hit the field, then die as a State Based Action. The reason is: when you use something like {yisan, the wandering bard}, to cast things like {genesis hydra} without paying the mana cost, X will be zero. So, he enters with 0 (+1/+1) counters, and you will look at the top Zero card of your deck.

[RDJDenley]

I was hoping for more of a positive answer haha. Many thanks for your help!

[Remillo]

Do note that with Yisan's ability, you never cast the creature.  You simply put it on to the battlefield.

[redwolv]

Yup, anything with X considers X to be 0 when checking its converted mana cost, last I heard.

[Gorzo]

Yup, anything with X considers X to be 0 when checking its converted mana cost, last I heard.

Yes. X is always considered 0 for CMC, except when on the stack.

If it's on the stack, x is x. If it's anywhere else, x is 0.

[Anoobass]

Small question on this X is 0 everywhere but the stack.

If I cast {hydra broodmaster}, then monstrosity X = 7.  If I were to populate a 7/7 hydra, would it be a 7/7 or would it be a 0/0 and die?

[LinkCelestrial]

Small question on this X is 0 everywhere but the stack.

If I cast {hydra broodmaster}, then monstrosity X = 7.  If I were to populate a 7/7 hydra, would it be a 7/7 or would it be a 0/0 and die?

You're copying the token, which is a 7/7. No effects would cause it to become a 0/0 (short of getting -7/-7'd) so the populated token would be a 7/7.

[Anoobass]

So on the battlefield X/X is no longer "X" but replaced by the actual value?

[Gorzo]

Correct. You'll notice that the actual hydra token in Journey into Nyx is represented with a */* and not an X/X. That's exactly why - the star represents an actual hard value on the battlefield (as determined by whatever effect, depending on the card, in this case it's locked in by {Hydra Broodmaster}'s Monstrosity ability).

The X in the ability is only representing the numeric value when the ability is on the stack, which upon resolution is replaced by (actual number) of tokens that have (actual number) of power and (actual number) of toughness.

[Anoobass]

Correct. You'll notice that the actual hydra token in Journey into Nyx is represented with a */* and not an X/X. That's exactly why - the star represents an actual hard value on the battlefield (as determined by whatever effect, depending on the card, in this case it's locked in by {Hydra Broodmaster}'s Monstrosity ability).

The X in the ability is only representing the numeric value when the ability is on the stack, which upon resolution is replaced by (actual number) of tokens that have (actual number) of power and (actual number) of toughness.

I never pulled the hydra token so I just assumed it had x/x printed which is why I was confused.  That being said, thank you for the explanation.