I think of (current) hydras more as green's phoenixes than its dragons. They're always big, flashy, and rare+, but the type is loosely tied to mechanics. All hydras tend to have a mechanic that represents multiple heads and/or regeneration, just as all phoenixes tend to have some sort of recursion ability.
Green needs its dragons. I'd suggest large flying insects, or even large swarms of insects, a la Hornet Queen, but luminum can is correct on green not getting flyers that often. Spiders would seem to work, but, much like baloths and other beasts, wurms, and elementals, the problem with spiders (and even insects) is that those types appear all the time on common creatures...
Altering what discarding does is changing the definition. Unlike "counter", "discard" is defined in the same way "dies" is (we're assuming) defined, as the movement of a card from Zone A to Zone B. So if your reasoning is correct, and Cyclopean Fortress doesn't work, then Obstinate Baloth doesn't work either.
First, you're right. That was very poor choice of words on my part.
Second, Obstinate Baloth, as well as Wilt-leaf Liege, do actually change what discarding means, but only because they have to, in the same way as madness (which I was actually wrong about before).
Compare:
Quote from Madness »
“If a player would discard this card, that player discards it, but may exile it instead of putting it into his or her graveyard.”
Quote from Obstinate Baloth (with the "opponent" clause removed) »
"If a player would discard this card, that player discards it, but puts it onto the battlefield instead of putting it into his or her graveyard."
If this wonky rule-breaking wording wasn't used, the cards would be functionally different. Consider these discard replacement effect using the "would" template:
"If a spell or ability an opponent controls would cause you to discard ~, put it onto the battlefield instead."
With this wording, after my opponent Raven's Crimes me and I put the card onto the battlefield instead of discarding it, I have to discard another card because I didn't actually discard a card yet.
Based on this, your wording might technically work (I'm not 100% positive, but I'm now pretty sure it would.), though I believe it should be worded much more like madness (Don't forget that reminder text doesn't actually mean anything) to make it absolutely clear what the unusual mechanic actually does:
"If Cyclopean Fortress would die, it dies, but is put on the bottom of its owner's library instead of being put it into his or her graveyard."
...but there is no precedent for it, nor is there much reason for it.
Nissa's Chosen is already a prime example of the effect you're looking for. Why deviate from that? Yes, the way you want the ability to work, it would still trigger abilities that trigger off creatures dying, whereas Nissa's Chosen wouldn't, but why is that necessary?
I'm not completely sure of the flavor of the card, but being that it's a creature that can only be cast from the graveyard and is put on the bottom of its owner's library instead of being put it into his or her graveyard, I feel like it probably wouldn't ever actually be "dying" anyways, so why jump through hoops to make it die?
Nissa's Chosen, at least from what I can deduce, isn't a creature that never dies, there's is just a lot of them, yet WOTC made the card so it never dies for simplicity's sake. Your card is a card that never "dies" and should have a card that never dies, simple as that. How often do you see cards that are already fairly complex with comments like, "too simple"?
So, in conclusion, the wording should really be:
"If Cyclopean Fortress would die, put it on the bottom of its owner's library instead of being put it into his or her graveyard."
...but, if you really, really want it to still functionally "die":
"If Cyclopean Fortress would die, it dies, but is put on the bottom of its owner's library instead of being put it into his or her graveyard."
Again, I don't mean to come off as rude. This has been quite a learning experience for me and, hopefully, for you as well. Between the two of us, we've delved deeper into the intricacies of Magic terms than I ever figured would ever be necessary.
However, I also cited the examples of Obstinate Baloth and madness, which do the same thing but for "discard". And the definition of "discard" (701.7) does state directly that to discard a card is to move it from the hand to the graveyard. As demonstrated by the cited examples, a replacement effect can actually change that definition while still leaving it a "discard". So my opinion remains that the wording works with "dies".
Madness doesn't change the definition:
Quote from Comp. Rules »
702.32a Madness is a keyword that represents two abilities. The first is a static ability that functions
while the card with madness is in a player’s hand. The second is a triggered ability that
functions when the first ability is applied. “Madness [cost]” means “If a player would discard
this card, that player discards it, but may exile it instead of putting it into his or her graveyard”
and “When this card is exiled this way, its owner may cast it by paying [cost] rather than paying
its mana cost. If that player doesn’t, he or she puts this card into his or her graveyard.”
Cards with madness, as well as Obstinate Baloth, have effects that alter what discarding does, similar to how Dissipate alters countering.
Prismatic (This card is all colors and can only be cast if only colored mana was spent to cast it.)
Hows that?
That looks much better to me. I would have never thought of that myself.
EDIT: In retrospect, I agree with luminum, though it still feels a tad bit off, to me, as a keyword. I think part of me wants it to be as elegant as changeling, but I'm not sure it can be without losing some of what makes it interesting...
Prismatic (This card is all colors. Only colored mana may be spent to cast this.)
Non-Eye creatures you control can't attack.
When Mind's Eye enters the battlefield, choose a color.
When Mind's Eye dies, gain control of target permanent of the chosen color.
[5/4]
Also, to me, at least, "This card is all colors." and "Only colored mana may be spent to cast this." seem odd together, but kind of seem odd apart from each other. Not sure what I'd do about it though...
Like the several plot points and final big battle of Agents of Artifice?
Just thinking out loud, but has a card with "Players can't discard cards" ever been printed?
Green needs its dragons. I'd suggest large flying insects, or even large swarms of insects, a la Hornet Queen, but luminum can is correct on green not getting flyers that often. Spiders would seem to work, but, much like baloths and other beasts, wurms, and elementals, the problem with spiders (and even insects) is that those types appear all the time on common creatures...
No, it wasn't.
No, but she could attack an opponent's planeswalker instead.
First, you're right. That was very poor choice of words on my part.
Second, Obstinate Baloth, as well as Wilt-leaf Liege, do actually change what discarding means, but only because they have to, in the same way as madness (which I was actually wrong about before).
Compare:
If this wonky rule-breaking wording wasn't used, the cards would be functionally different. Consider these discard replacement effect using the "would" template:
With this wording, after my opponent Raven's Crimes me and I put the card onto the battlefield instead of discarding it, I have to discard another card because I didn't actually discard a card yet.
Based on this, your wording might technically work (I'm not 100% positive, but I'm now pretty sure it would.), though I believe it should be worded much more like madness (Don't forget that reminder text doesn't actually mean anything) to make it absolutely clear what the unusual mechanic actually does:
...but there is no precedent for it, nor is there much reason for it.
Nissa's Chosen is already a prime example of the effect you're looking for. Why deviate from that? Yes, the way you want the ability to work, it would still trigger abilities that trigger off creatures dying, whereas Nissa's Chosen wouldn't, but why is that necessary?
I'm not completely sure of the flavor of the card, but being that it's a creature that can only be cast from the graveyard and is put on the bottom of its owner's library instead of being put it into his or her graveyard, I feel like it probably wouldn't ever actually be "dying" anyways, so why jump through hoops to make it die?
Nissa's Chosen, at least from what I can deduce, isn't a creature that never dies, there's is just a lot of them, yet WOTC made the card so it never dies for simplicity's sake. Your card is a card that never "dies" and should have a card that never dies, simple as that. How often do you see cards that are already fairly complex with comments like, "too simple"?
So, in conclusion, the wording should really be:
...but, if you really, really want it to still functionally "die":
Again, I don't mean to come off as rude. This has been quite a learning experience for me and, hopefully, for you as well. Between the two of us, we've delved deeper into the intricacies of Magic terms than I ever figured would ever be necessary.
Don't forget to put it on lots of vampires and berserkers.
Madness doesn't change the definition:
Cards with madness, as well as Obstinate Baloth, have effects that alter what discarding does, similar to how Dissipate alters countering.
I like it. It's as if the creature itself summoned the cat and is now holding the "leash."
That looks much better to me. I would have never thought of that myself.EDIT: In retrospect, I agree with luminum, though it still feels a tad bit off, to me, as a keyword. I think part of me wants it to be as elegant as changeling, but I'm not sure it can be without losing some of what makes it interesting...
Also, to me, at least, "This card is all colors." and "Only colored mana may be spent to cast this." seem odd together, but kind of seem odd apart from each other. Not sure what I'd do about it though...