Aside from the obvious Helm of the Host, you have options
While the efficient ones tend to be the strongest, there are also quite a few expensive counterspells that pack a punch
Virtue of Knowledge Double your something Virtue of Knowledge is a five-mana enchantment that makes it so that if a permanent enters the battlefield and causes a triggered ability on one of your permanents, that trigger happens twice
If you're hoping to open maximum value from this set, however, these are the cards to hope for - just be aware that in some cases, certain printings will only show up in Collector Boosters
Target player draws two cards
This sets up Soul Foundrys linked activated ability, which states that by tapping and paying X mana, with X equal to the converted cost of the creature, you get to put a copy of that creature into play