Ideas for new dual quantum cards

[Demongod]

Rule: only at most 6 in the deck.  Ideas are from cards already using twin mana requirements.

Upgrades work like towers.

Volcano: adds Earth/Fire every turn. 
Dimensional rift: adds Time/Aether every turn.
Timeless sands: adds Time/Earth every turn.
Magic river: adds Water/Aether every turn.
Magnetic Mountain: adds Gravity/Earth every turn.
Holy tower: Adds Light/Time every turn.
Sunlit Garden: Adds Light/Life every turn.
Elevated Grove: Adds Wind/Life every turn.
Shadowed tower: Adds death/darkness every turn.
Coastal cliff: Adds earth/water every turn.
Immortal crag: Adds Time/Gravity every turn.
Enchanted Forest: Adds Chaos/Life every turn.

Ideally, there would be 12c2 of these (equals 66).  But for now, these are all of the ones which would already have a place in the game.

[Uncle Jellyfish]

I believe that Jmizzle already has a thread about this idea, based off of the dual-land system from M:tG.

[Forfeit]

And he has a chart and everything, I think the title is something like 'splash towers', not sure, you should go look, see if you have an opinion to put into it.