This is a deck built around dropping Heimerdinger on turn 5-6 every game, by cutting all units that aren't Heimerdinger or Vanguard Redeemer. This is because Redeemer only draws units, so you can reliably pull Heimerdinger after a Scrapdash Scuttler or Vanguard dies.
Mulligan for Heimer, Vanguard, and Flash of Brilliance, and some matchup-specific removal. Try to keep 3 spell mana for turn 5-6 when you're playing Heimerdinger, so you can play Flash on the same turn alongside some other 3 mana options. 3 mana is really important because it summons the best turret, the elusive one.