Because decks with Gaeas Cradle tend to search for Gaeas Cradle pretty reliably and you can assemble this combo whenever you get a witness with Cradle and enough creatures if youve already cast Snap, I try to play Snap as one of my interactive spells in any deck with Gaeas Cradle
Its an attack trigger, after all, so it doesnt need to connect
Simply put, this allows you to be aggressive when taking mulligans, aiming to get as many Tron pieces as you can with each iteration
You're not even spending a card with flashback, and the 10 mana can be generated via cards like Nykthos, Shrine to Nyx or Nissa, Who Shakes the World
With a good output, these decks leave no chance to less powerful decks
[Activate: Main] [Once Per Turn] Give up to 1 of your opponent's Characters 1000 power during this turn