Boreal Centaur

Flying, vigilance T: When target creature other than this creature dies this turn, return that card to the battlefield under your control.

Flying S: This creature gains first strike until end of turn. (S can be paid with one mana from a snow source.)

Cumulative upkeep S (At the beginning of your upkeep, put an age counter on this permanent, then sacrifice it unless you pay its upkeep cost for each age counter on it. S can be paid with one mana from a snow source.) If a creature would deal combat damage to you and/or one or more creatures you control, prevent X of that damage, where X is the number of age counters on this enchantment. S: Put an age counter on this enchantment.

Whenever you're dealt damage, you may create that many 1/1 white Soldier creature tokens.

Other Soldier creatures get +1/+1 and have first strike. (They deal combat damage before creatures without first strike.)

Enchant creature Enchanted creature can't block, and its activated abilities can't be activated. S: Enchanted creature gains defender until end of turn. (S can be paid with one mana from a snow source.)

Enchant creature Cumulative upkeep S (At the beginning of your upkeep, put an age counter on this permanent, then sacrifice it unless you pay its upkeep cost for each age counter on it. S can be paid with one mana from a snow source.) Enchanted creature gets +3/+3 for each age counter on this Aura.

Cumulative upkeep—Put two cards from a single graveyard on the bottom of their owner's library. (At the beginning of your upkeep, put an age counter on this permanent, then sacrifice it unless you pay its upkeep cost for each age counter on it.)