Myriad on my best creature each turn lets me make a big impact on the game, that and the combination of first strike, vigilance, and trample might be my favorite
Subira is kind of like Red's version of Edric, Spymaster of Trest, supporting Weenie decks by providing tons of card draw potential
Analysis: Boosts creature strength through +1/+1 counters, enhancing subsequent plays
Rowan, Scion of War Keep hitting yourself Rowan, Scion of War is a three-mana Black and Red 4/2 with menace, which means it can only be blocked by two or more creatures
While this is unlikely to be of any use to an aggressive deck or one that makes use of graveyard strategies, any deck that likes to take its time is probably going to want this around
You could target anything from a creature to enchantment, or another planeswalker, whatever is giving you the most trouble at the time