Of course, you can't mention Heliod, Sun-Crowned without mentioning the famous combo of it and Walking Ballista
While Prophet of Kruphix annoyed people by letting us take every turn by virtue of untapping our mana and letting us play spells as though they had flash, Engine doesnt aim to stick around, necessarily
But if you offer an opponent a card draw as a gift, your board gets indestructible as well
You already have two better equipment for the deck (Plating and Clamp) and equipment (and now vehicles) have diminishing returns
The ability to constantly cast permanents from your graveyard gives you incredible recursion, but theyre also a Commander who suits midrange style decks a little bit better, and were after something a little more aggressive
Its even better in a BG deck where you can take an extra turn, such as Alrunds Epiphany