While Foundations merely upgraded Shock to Burst Lightning, the deck has also cemented itself as a top-tier strategy in the current Standard metagame
For just 1 mana, it makes every opponent discard and lose life right away, then later cashes in for a scry to smooth your draws
People played Shrine of the Forsaken Gods and were happy about it, and it literally only made two mana if you were casting Ulamog, the Ceaseless Hunger
Mesa Enchantress and Satyr Enchanter These two fill essentially the same role
It is a gamble, similar to making an attack against Arthur in Risk so Betty can finish off a territory and deny Arthur the extra troops at the start of his turn
You generally play less early creatures if your deck would rather cast Sol Ring, Arcane Signet, or Commander's Sphere to reach a higher cost card