I don't know if this is a stupid question, but would these cards be legal in compliance with existing MTG rules? If not then what changes could be made to make them legal while still maintaining the same basic effect (assuming it's possible)? Also (and this probably isn't the place to ask), would they be at all viable?
Mana Crisis 2RB
Enchantment - Aura
Enchant player
During enchanted player's upkeep, the player that controls Mana Crisis may pay X. If they do, enchanted player may not have more than 10-X mana in their mana pool at any one time during that turn. X may not be greater than 6.
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Mana Abundance 2GU
Enchantment - Aura
Enchant player
Any unspent mana in enchanted player's mana pool at end of their turn carries over to their next turn.
I don't think there are any cards or rules that currently limit the amount of mana that can be in a player's mana pool. WotC tries to avoid preventing players from using mana abilities (split second for example, although that was also to allow morph to still be payable), so there might be some deeper mechanical reason not to do this.
Theoretically you could still use mana abilities under Mana Crisis, they just wouldn't add mana beyond four to your pool. This could be relevant for cards like Zhur-Taa Druid.
On the other hand, I don't see why Mana Crisis couldn't just be reworked and say:
Enchanted player can't cast spells with converted mana cost 5 or greater.
Enchanted player can't activate abilities that cost 5 or more mana to activate.
I'm not entirely sure if that second line is as elegant as it could be, but it gets the meaning across. Outside of largely irrelevant oddness like Omnath and Doubling Cube, I don't see the functional difference between the above and Mana Crisis.
Edit: Oops, total necro. Wasn't paying enough attention. Hopefully somebody finds this useful in some way?
Mana Crisis
2RB
Enchantment - Aura
Enchant player
During enchanted player's upkeep, the player that controls Mana Crisis may pay X. If they do, enchanted player may not have more than 10-X mana in their mana pool at any one time during that turn. X may not be greater than 6.
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Mana Abundance
2GU
Enchantment - Aura
Enchant player
Any unspent mana in enchanted player's mana pool at end of their turn carries over to their next turn.
Mana Abundance
2GU
Enchantment - Aura
Enchant player
Mana doesn't empty from enchanted player's mana pool as steps and phases end.
Thank you. That is good to know. I guess that wording covers more loopholes. So would the Mana Crisis idea be a legal card?
On the other hand, I don't see why Mana Crisis couldn't just be reworked and say:
I'm not entirely sure if that second line is as elegant as it could be, but it gets the meaning across. Outside of largely irrelevant oddness like Omnath and Doubling Cube, I don't see the functional difference between the above and Mana Crisis.
Edit: Oops, total necro. Wasn't paying enough attention. Hopefully somebody finds this useful in some way?