Since we know that a straight comes-into-play-tapped-dual (Cinder Barrens) is low enough power that it can gain a relevant type like Gate or etb gain 1 life and still be more common than common, I think that it could also be appropriate as a 2-color MDFC. The questions to balance are (a) should the other side be true multi-color or hybrid and (b) how aggressively costed can the spell be without breaking it? Should the spells be more narrow or generally useful? I'm thinking uncommon power level for this.
Kin-Tree Blessing
WG
Instant
Destroy target artifact or enchantment.
//
Kin-Tree Sanctuary
Land
CARDNAME enters the battlefield tapped
T: Add G or W
I think the spell side can be generally useful spells, if potentially somewhat limited or situational. In this instance, with the spell being multicolor and not hybrid, I think it's costed fairly as it's technically more difficult to cast than Disenchant or Naturalize. If it were hybrid, it'd have to go up in cost or maybe be slowed to sorcery speed?
In terms of aggressive costing generally, I think MDFCs do require the spell side be less efficient as a trade-off for the added flexibility. I think making things sorceries rather than instants can help reduce how much more expensive the cost can be. Ditto with increased color requirements (where applicable), though your mileage may vary as monocolored spells with higher color needs aren't always a major drawback or balance dial. I think if the spell is much more narrow in effect, it can probably be more in line with how it'd be costed if it were not an MDFC, with mind still paid to the flexibility inherent in MDFCs.
I'm kinda on the same page. I think it should definitely be a true 2 colored spell, and a little over costed of the effect, but not quite a narrow as just a disenchant.
Kin-Tree Sage
2GW
Creature - Human Warrior
When CARDNAME enters the battlefield, destroy target artifact or enchantment.
2/1
//
Kin-Tree Sanctuary
Land
CARDNAME enters the battlefield tapped
T: Add G or W
Maybe the Sage could be 1GW since its 2 colors and not an elf? Or maybe as is but a 2/2? Costing is tricky.
Sage could easily be a 2/2 at that price. Even 2/3 or 3/1 wouldn't be out of the question. At 1GW, it can be 2/1 as it's a 'worse' Reclamation Sage where the ability to play it as a dual instead justifies it.
It's a worthwhile exploration of MDFCs. I like that it's a dual to fix you if you didn't draw into one of your colors, and it's a decent spell if you're good on mana. It's also a really neat way of bolstering a multicolor set's number of multicolor cards while also providing the manabase decks in Limited require in that environment.
Kin-Tree Blessing
WG
Instant
Destroy target artifact or enchantment.
//
Kin-Tree Sanctuary
Land
CARDNAME enters the battlefield tapped
T: Add G or W
In terms of aggressive costing generally, I think MDFCs do require the spell side be less efficient as a trade-off for the added flexibility. I think making things sorceries rather than instants can help reduce how much more expensive the cost can be. Ditto with increased color requirements (where applicable), though your mileage may vary as monocolored spells with higher color needs aren't always a major drawback or balance dial. I think if the spell is much more narrow in effect, it can probably be more in line with how it'd be costed if it were not an MDFC, with mind still paid to the flexibility inherent in MDFCs.
Archatmos
Excellion
Fracture: Israfiel (WBR), Wujal (URG), Valedon (GUB), Amduat (BGW), Paladris (RWU)
Collision (Set Two of the Fracture Block)
Quest for the Forsaken (Set Two of the Excellion Block)
Katingal: Plane of Chains
Kin-Tree Sage
2GW
Creature - Human Warrior
When CARDNAME enters the battlefield, destroy target artifact or enchantment.
2/1
//
Kin-Tree Sanctuary
Land
CARDNAME enters the battlefield tapped
T: Add G or W
Maybe the Sage could be 1GW since its 2 colors and not an elf? Or maybe as is but a 2/2? Costing is tricky.
It's a worthwhile exploration of MDFCs. I like that it's a dual to fix you if you didn't draw into one of your colors, and it's a decent spell if you're good on mana. It's also a really neat way of bolstering a multicolor set's number of multicolor cards while also providing the manabase decks in Limited require in that environment.
Archatmos
Excellion
Fracture: Israfiel (WBR), Wujal (URG), Valedon (GUB), Amduat (BGW), Paladris (RWU)
Collision (Set Two of the Fracture Block)
Quest for the Forsaken (Set Two of the Excellion Block)
Katingal: Plane of Chains