mtg is legendary a card type Baral and Kari Zev (Showcase Planar Booster Fun) [March of the Machine Does Shelob's effect include legendary

Pantlaza's Discover ability means that each dinosaur you cast has the potential to trigger a cascade, letting you fetch up one or potentially more other random dinosaurs from your deck (worst case scenario you hit a mana rock or something)

Spend this mana only to cast Elemental spells or activate abilities of Elemental sources

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Flying attackers are just the chefs kiss in a combat scenario

Check out other decks of a similar power level with relatively good Rare and above cards - MTG Arena Starter Decks

In deciding which deck is for you, you'll first want to get a general idea of what its core archetype, themes, and mechanics