(putrid imp, basking rootwalla, gravecrawler, gravescrabbler are all fun with this card and vengevine).
But the most use for me lies in dredge: turn 1 breaktrough: discard hand while breaktrough is on the stack, dredge a lot, flashback faithless looting with the 3 red mana from this card and dredge more! (Like half your deck in your gy in turn 1 works pretty well :))
Play a draw/tutor card, keep priority and crack this in response !
This goes great with Madness, Threshold, Delirium, Delve, Dredge, Flashback, tutors and reanimator.
Crack this, discarding your hand and enabling Madness triggers. Then use your 3 mana to pay for Madness costs. You could have an Arrogant Wurm in play on turn 1 with this.
You can drop a land, crack this, dump Unburial Rites and a fattie in the graveyard and Flashback Rites bringing that fattie into play on turn 1.
When this card came out, it sucked. There was almost nothing you could do with it. 20 years later, it's a "build-around me" Black Lotus. A lot narrower, but easily breakable.