If that creature would die this turn, exile it instead
Essentially, if you have a full party with all four of these on the board, you can pay one white, one blue, and one black mana to give the Warrior lifelink, deathtouch, and make him unblockable (deathtouch and unblockable at the same time has no real use, but thats still OP to think about)
Wizards of the Coast also probably wanted to exhibit a series of great pieces of art to show off some of the famous locales from various entries in the Final Fantasy series
Play Boosters deliver Standard playables with bonus foils, while Collector Boosters emphasize premium frames and serialized cards
Slaughter is never going to make our guide to the best MTG cards, but one of the wonderful things about Commander is how it turns niche cards into powerhouses