Removing a game-ending threat for one mana represents incredible value even when opponents gain 10+ life, since dead players gain no life at all
Product Details Any creature in either players graveyard comes into play on your side with -1 to its original power
If this causes the number of historic cards in your graveyard to change (probably because you are casting The Capitoline Triad from your graveyard), that new number will be used to determine the cost reduction
The deck features 32 different legendary creatures and 8 legendary planeswalkers that can generate tons of value through powerful effects including generating creature tokens (Faldorn, Garth, Jenson, Minsc, General Ferrous Rokiric, Kari Zev, etc), casting free spells (Etali), generating creatures abilities or buffs including +1/+1 counters, first strike, flying, deathtouch, double strike, haste, hexproof, cascade, indestructible, lifelink, menace, reach, trample, vigilance (Halana and Alena, Odric, Surrak, Marchesa, Garna, Imoti, Raff), tutor abilities/card draw (Sisay, Kolvori, Niambi, Vega), Buffing your army (Jodah, Rienne, Arvad), and many more
Lets not get too negative, though