The Butterfly Effect: Comments

these cards seem interesting but a bit confusing, guessing it'll make more sense once more cards are here. the artifact subtypes and the spell supertype seem like interesting design choices. are you going to leverage these or is it more of a "it's my magic set so i can develop my own taxonomy and this makes more sense" thing?

I was debating between red and black for this effect as its a sacrifice something to deal damage to something, but goblins are traditionally red, so I went with that. Any ideas? My other ideas were using red, green, and black as the "traditional" slave ideals, white for an archetype of defending the slaves, and blue for some other effects.

You should write the proper definition and rules for "slave" (and other things used in this set, if any) in a details section. Some cards capitalize "Slave" (suggesting that it is a creature type) and some don't, so it is unclear. Two cards mention '"slave" tag', but I don't know what a '"slave" tag' is. Some other things also are not written very well.