I also advise steering clear of most cards that only gain life, like Feed the Clan and Natural Spring
Boros Convoke is a dependable Standard MTG deck that does a good job avoiding the loss of steam that some aggro decks suffer from, and can even do well against board wipes thanks to lots of different tokens
This helps you plan your future turns and play around their strategy and alter yours so you don't play into certain spells
Early expansions aren't particularly consistent with it, but later on most human soldiers would hover around the level of a 2/2 stat line
You have your level shown at the top of your screen, and each time complete an appropriate action, EXP is earned
Many hove strong abilities that generate value by creating creature tokens and/or directly helping crew more vehicles (Shorikai, Parhelion, Peacewalker, etc), draw cards, deal direct damage, accelerate your mana, and more