mtg cards like heroic intervention TappedOut Your deck of cards represents all the weapons in your arsenal MTG - Heroic Intervention -

Once each turn, including on your opponents' turns, you can cast a spell with mana value X or less for free where X is the number of time counters on As Foretold

The Secret Lair drops themselves are significantly increasing the supply of some of these cards (we have already seen the original printings of some Secret Lair reprints dropping in price, like Marrow-Gnawer), and even if Magic continues to grow, the supply of these reprints is high enough that, at least for most, it's unlikely they will explode in price in the near future

There are also a lot of good cards that give this effect, such as the mighty Flickerwisp, but only ten can make it into the best flicker cards in MTG

Sounds great

#3 Entangler Set: Prophecy Printing: Normal Increase: +$8.75 Current Market Price: $10.04 This forgotten Uncommon from 2000 was suddenly thrust into the limelight by the release of Marvels Spider-Man and the popular new commander Anti-Venom, Horrifying Healer