Just an idea that was rattling around in my brain. I'm sure I can't be the first person to think of it.

There was a piece on Maro's podcast recently; they were going to do non-creature morph, but it played really badly when you also had morph in the same environment. (Because morph you want to block and spell-morph you never want to)

Putting this in exile instead is an interesting variation. Though this is costed so hard it will only ever be used in its morph-form, which seems a shame.

Well, your opponent will alwayys see the trap being laid, so that's why this exact mechanic - which has been suggested dozens of times - is often not used over alternatives e. g. Trap spells with conditional cost reduction.

I think it's fine if among the less desirable custom mechanics. Nothing I would put in the "never to be done" pile, but with its issues.

Yeah, coming up with a proper cost for anything with morph can be tricky. If you want the morph part to be efficient, you need to make the alternative option be unwelcoming.

Probably could have been anyway. Like SecretInfiltrator mentioned, the big problem with Spelltrap is that you see it coming. Giving players the ability to pay more if they want to surprise someone seems relevant.

I would also point out that the ability to see something coming, but not know exactly what it is is the whole fun behind the morph mechanic in the first place. I don't think that's what's holding the mechanic back. I'm pretty sure it's just an implementation issue.

Morph has the big benefit that the face-down card has an inherent use - so sometimes you don't know whether the face-down card is actually a trap lying in wait for you or whether your opponent just wanted to use their mana efficiently or is placing a chump blocker.

Without this inherent use spelltrap is all about the cas´ting from exile.

Which is btw, why I liked a similar mechanic, where you could play your land as what you could call a face-down Waste - but a spell on the reverse side: terramorph.

Another thing I could imagine are spells that you could "charge up" while they are face down in exile e. g. by placing multiple trap counters on them over time - your opponent wouldn't know when your trap was fully set.

There needs to be some level where the face-down card's intention is obscured - which is why some morphs are simply vanilla why others are reactive.

Generally the flavor of traps is a trap for magic designers. What is a trap? It's usually hidden. Well the player's hand in magic is already a hidden zone. So why would you put a card from hidden zone into a public zone, and still call it a trap?

Huh, the morph lands are an interesting idea. You're right that it's an uphill struggle to make non-creature morphs relevant, even though I keep being interested in the idea.

@amuseum: You would have to ask the designers of Yu-Gi-Oh and Hearthstone the same thing. Or for that matter, the designers of Dungeons and Dragons adventures like Tomb of Horrors. Knowing a trap exists, but not being sure what it does, doesn't make the trap less interesting or exciting.

As a matter of fact, the difference between a trap in hand, and a trap on the table is pretty much Alfred Hitchcock's definition of the difference between Surprise and Suspense. If you cast a spell when your opponent triggers a specific event, but they didn't know it was coming, that's a surprise. If there's a face down trap, but you don't know exactly what's going to trigger it, that causes suspense (and potentially surprise if you were wrong about the trap.)

This isn't really a 'use one, not the other' issue. Sometimes surprise is good, and sometimes suspense is good. Liking one over the other doesn't mean the other shouldn't be used too.

The argument though is, I believe, that a trapper wants the trap to be a surprise - the story teller may want suspense, but that's a different thing.

Hitchcock might "tell" the audience about the trap to make them feel suspense, but that doesn't mean the in-universe character/victim of the trap needs to know beforehand to know about it.

From a gameplay point of view the opponent is walking into a trap, if it's a surprise. Suspense is more accurately created by a(n unknown) threat - which is one of the ways Innistrad created "horror"/suspense.

tl; dr: The question is whether the opponent should be considered part of the audience or the victim. If they are considered the victim, then something you tell them beforehand feels less like a trap and more like a threat.

Trap:surprise::threat:suspense.

A musing on the idea: Mana Accumulator.

I think having the opponent know there's some sort of surprise coming but not knowing which one works pretty well, and people have tried to make this work with designs I quite like before (like Alex's 'prepare' in Code Geass). But the problem SI points out is because practically, players play much fewer non-creatures, so if there's a face down non-creature, it's probably because it's supposed to be a nasty surprise, which narrows the possibilities. And as someone else pointed out, its owner will only do that if they have to or get a cost reduction or similar, which narrows the design space. So I want to see this work but I acknowledge the difficulty.

A good test is probably "can you design enough commons with this ability that players are genuinely unsure which one their opponent has played"?