MORPH -An MTG morph effect could work in theory, but only if enough cards were created to make it hard for the opponent to reliably know what was going on. For example, if there is only one 2
hidden card, and the opponent plays an 'unknown' 2
costing card, well, gee, I wonder what they just played? You could make all of them cost the same, either an in-element cost like 3
or 3
, or else have everything be an 'other' card and cost something like 5
, but having an other cost creates a host of other balance problems, unless the cards aren't particularly strong. (see current other cards, shield, short sword, hammer, etc) Given the rate of new cards, the only viable solution in the short term would be an across the board uniform other cost, which I don't like.
The Dragon's Demesne
Other Permanent
3
cost to play
8
: Flip this card up and discard it. Place a random dragon into play on your side.
TRAP - A 'trap' mechanic. This would have a few ways of implementing. One could play it for 0 cost, and have it trigger on some given condition (creature dying, life gained, full hand, spell cast, etc) if a particular quanta cost can be played. For example, consider the following card:
Zanzarino's Revenge
Gravity Permanent
Cost = 0
When opponent kills one of your creatures, if you have at least 5
in your pool, lose 5
and this card is sacrificed. Your opponent takes damage equal to that creature's hp.
It would still be obvious in a mono if this was the only gravity one, but if there were a couple of them, or you were playing more than one element, it could be harder to figure it out, although a good player could probably analyse deck strategy and still figure it out most of the time.
TARGETING: I'm imagining this working somewhat like the original wording of MTG's Illusionary Mask. (not the BS errataed version) Or perhaps MTG's Camouflage. Imagine a card like this:
Camouflage (yes, plagiarism, I know...)
Life spell
3
cost
When Camouflage is cast, flip all your creatures facedown and shuffle them randomly on your field. Reveal them only if targeted by a spell or effect. New creatures played afterwards are played face up.