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Should the token have flying?

I like the design either way, but I think I like it more with flying. Sortof feels like this should have defender itself - so it only attacks through its projections. It might be more use in combos if you just always make the token and sacrifice the token at end of turn / end of combat... but I'm not sure if that's a direction you want to push this or not.

Creating a token that gets sacrificed at end of turn was the original idea, but I wanted to see whether I could do something new.

Defender is deifinitely an option, but lack of flying was entirely an unintended omission.

This is a really cool card. But compare this to Phantom Warrior. Two hard to block damage every turn shouldn't cost .

Granted, there are other reasons why you would want the Thopter. Sacrificing an artifact every turn, for example. Which is why I'd probably cost it as . But I would definitely make sure there were other things in set with it to combo with.

I think two hard-to-block damage every turn along with some other utility absolutely can cost . I'm reminded of Azorius Knight-Arbiter, which admittedly is common rather than uncommon; in that case the utility you get is "block a 4-power creature each turn as well". Gold cards get to be cheaper than colourless cards too - Flying Menace, I mean Sky Terror, is an extreme example.