Tinker is a good mechanic and it tested well during the first run at these decks.

• Tinker (When this permanent enters, you may sacrifice an artifact.)

This makes the Science deck a straightforward artifact deck and distinguishes it from spell-themed Izzet. It leans heavily into engineering creative.

I do not shy away from brainstorming alternative mechanical space. I think about what a card with the subtype Discovery or Thesis might do/be.

First Question: What should be the new central mechanic of the Faith deck?

• While the mechanical direction of the deck might be salvageable (go-wide + life gain), the actual keyword ability/action that was tested is bad
• OLD VERSION: pray (You gain 1 life for each creature you control.)

I'm mentally working on a version of investigate/amass/the Ring tempts you to replace the pray effect. More as ideas become more concrete.

It should be noted that the Faith deck was mechanically diverse and had a mechanic called literally Faith which now after TDM would be written as "behold an Angel".

I consider "behold X" as an option for a shared mechanic between the decks, and independently I think the phrase "behold a Miracle" is fun and I want to use it on a card - not necessarily in this product. :)