You get a full two turns to play these cards so the impulse effect is fairly lenient and because at the time of writing this card has been recently printed, it's very accessible too, much cheaper than the identical Reckless Impulse
Urborg, Tomb of Yawgmoth You may be familiar with Urborg, Tomb of Yawgmoth in Commander as it pairs well with Cabal Coffers, but the Legendary Land is effective in Pioneer
The idea is that by paralyzing the opponents Pokemon with Pincurchin and putting it to sleep with Hypno, I might be able to stall the game out long enough to power up one or two Zapdos ex, then finish the game quickly once my big mean birds are in play
Obviously exiling instead of sacrificing is a big deal, but Sothera requires everyone to have creatures in play for it to stick around
Llanowar Elves has a sweet Secret Lair version that might be the right nonfoil choice
I got a nice binder collection going in 99