The game doesn't check for lethal damage during the resolution of a spell or ability, only after the spell has resolved, and at that point, the Magnivore has 5 toughness, since the Blaze is in the graveyard
Then when the final chapter of a Saga resolves, you can reveal your library until you reveal a Saga and put it into the battlefield for free
If you wanted to use snow basics, you could add Into the North
Each Booster contains a total of 20 cards: 1 Legendary creature or planeswalker (rare or mythic rare in 31% of boosters) 1 Legendary Background (rare in 1 of 12 boosters) 1 Non-legendary rare or mythic rare card 3 Uncommons 13 Commons 1 Traditional foil card of any rarity 1 Token, ad card, or dungeon card When you're drafting Commander Legends: Battle for Baldur's Gate , you'll take two cards at a time and build a Commander deck containing a minimum of 60 cards
Pretty strong stuff
Look through the most popular removal spells in Modern almost none of them can kill Elesh Norn