Serious-wise though, what would your opinion be on a sub-series of cards with the Duality Cost, but mark-dependent abilities?
They would be a terrible vehicle for ideas.
by vehicle do you a way to carry out ideas?
it would be a great brainstorming process anyway for new ways to synergize
A vehicle is the backbone/structure upon which various alterations and variations of abilities can be applied.
Creature/Spell/Permanent are vehicles upon which effects can be added
Elemental/Other are vehicles upon which cards can be added
Weapon/Shield/Pillar are vehicles upon which effects can be added
Doom Clock Permanents/Creatures (Dimensional Shield, Sundial) are vehicles upon which creatures or permanents can be added
Absorb Cost Permanents/Creatures (Flooding, Ajit's Mage Series) are vehicles upon which creatures or permanents can be added
Automatic Active Skills, Activated Active Skills and Passive Skills are vehicles upon which skills may be added
The problem is that Hybrid costs and Mark Dependant skills when combined make the result have lower quality than 2 separate cards using the normal mono static skill vehicle.