This card is going to be a great one for the future and has come down in value quite a bit since its release
Tifa's last ability cares about the power of each individual creature that dealt combat damage to a player, not their total power
Next, you need to work out what you want your deck to do, based on the different Magic: The Gathering deck types out there
WOTC did a fantastic job with the flavor here
Aang, Airbending Master Aeronaut Cavalry Aetherstorm Roc Anafenza, Kin-Tree Spirit Aquastrand Spider Arcbound Crusher Archpriest of Shadows Arwen, Mortal Queen Basri's Lieutenant Benevolent Hydra Bloodline Pretender Bojuka Brigand Bola Slinger Boon-Bringer Valkyrie Boss's Chauffeur Botanical Brawler Breathless Knight Bright-Palm, Soul Awakener Calix, Guided by Fate Celebrity Fencer Champion of Lambholt Champion of the Hareish (playtest) Champion of the Parish Champion of the Perished Charforger Chomping Kavu Cleric of Life's Bond Combine Guildmage Conclave Sledge-Captain Consuming Aetherborn Contagion Clasp Contagion Engine Cytoplast Manipulator Cytoplast Root-Kin Death-Greeter's Champion Decorated Champion Defiant Greatmaw Demonlord of Ashmouth Elvish Vanguard Emcee Emiel the Blessed Enduring Bondwarden Evolving Adaptive Ezuri, Claw of Progress Fearless Skald Filigree Vector Flayer of the Hatebound Flensing Raptor Forerunner of the Heralds Gala Greeters Galadriel, Gift-Giver Galadriel, Light of Valinor Gimli of the Glittering Caves Glorifier of Suffering Golden-Scale Aeronaut Good-Fortune Unicorn Grakmaw, Skyclave Ravager Graypelt Hunter Grimgrin, Corpse-Born Gruul Beastmaster Guardian Scalelord Guide of Souls Hada Freeblade Hangar Scrounger Haru, Hidden Talent Helium Squirter Heronblade Elite Hexavus Indoctrination Attendant Ivy Lane Denizen Jackknight Jade Bearer
