Okay, once again a more casual list, but I think there’s a seed of something here.
There’s plenty of other options. If you want to go more black, both Mardu Shadowspear and Bloodsoaked Champion would be great. However, its better to just splash one of the colors. This could work even better as a purely red list:
Or with white:
I think the Vaultbreaker in each of these lists is a key card, because it can help dig for the Purphoros, without which the decks are just trying to go wide.