A first look at the red cards reveals two reprints from older editions, including Anger and Gratuitous Violence
Masters sets always have some oddball color combinations that either lack a particularly coherent archetype (RG in MMA2013), have a low average ceiling (UR Elementals in MMA2015, BG Dredge in MMA2013) or are so flexible as to not really have have an archetype (WB in EMA)
Goblin Guide [Extremely Fast and Early Pressure] Most red decks thrive on aggression, and Goblin Guide is one of the strongest red creatures in MTG for that purpose
If a face-down permanent you control leaves the battlefield, or if the game ends or you leave the game while you control it, you must reveal it to all players (even though in this case, everyone saw it before it entered)
Upon attacking with Bruna, you are able to put any number of auras onto her from your hand and graveyard
This creature is really inefficient