This spell costs
less to
castTo cast a spell is to take it from the zone it’s in (usually the hand), put it on the stack, and pay its costs, so that it will eventually resolve and have its effect. A player may cast a spell if they have priority. See rule 601, “Casting Spells.”
To cast a card is to cast it as a spell. (CR 701.5) for each instant and sorcery card in your graveyard.
ReachReach is a static ability.
A creature with flying can’t be blocked except by creatures with flying and/or reach. (See rule 509, “Declare Blockers Step,” and rule 702.9, “Flying.”)
Multiple instances of reach on the same creature are redundant. (CR 702.17)
Whenever The Dawning Archaic attacks, you may
castTo cast a spell is to take it from the zone it’s in (usually the hand), put it on the stack, and pay its costs, so that it will eventually resolve and have its effect. A player may cast a spell if they have priority. See rule 601, “Casting Spells.”
To cast a card is to cast it as a spell. (CR 701.5) target instant or sorcery card from your graveyard without paying its mana cost. If that spell would be put into your graveyard,
exileTo exile an object, move it to the exile zone from wherever it is. See rule 406, “Exile.” (CR 701.13) it instead.