FlyingFlying is an evasion ability.
A creature with flying can’t be blocked except by creatures with flying and/or reach. A creature with flying can block a creature with or without flying. (See rule 509, “Declare Blockers Step,” and rule 702.17, “Reach.”)
Multiple instances of flying on the same creature are redundant. (CR 702.9)
Whenever The Vast Scrier attacks a player, you may put a Soldier, Warrior, or Wizard creature card from your hand onto the battlefield tapped and attacking that player. If it has any "Whenever this creature attacks" triggers, those trigger. If you don't put a card onto the battlefield this way,
scryTo “scry N” means to look at the top N cards of your library, then put any number of them on the bottom of your library in any order and the rest on top of your library in any order.
If a player is instructed to scry 0, no scry event occurs. Abilities that trigger whenever a player scries won’t trigger.
If multiple players scry at once, each of those players looks at the top cards of their library at the same time. Those players decide in APNAP order (see rule 101.4) where to put those cards, then those cards move at the same time.
An ability that triggers whenever a player scries triggers after the process described in rule 701.22a is complete, even if some or all of those actions were impossible. (CR 701.22) 2.