It has Evasive, which means only other cards with the Evasive ability can challenge it while its questing for Lore, and it gains 3 Strength when challenging other characters with its Challenger ability
however, value-wise, I would say that this Lairs biggest draw would be the foil Field of the Dead (Cabin of the Dead)
Before the bans, Heartfire Hero was arguably one of the best 1-drops in the format because it's a 1/1 creature with Valiant, meaning it gets +1/+1 counters easily, and then deals damage equal to its power to all opponents on death
Fill your deck with cheap Elves, sacrifice outlets, and cards that dump creatures into your graveyard
And while we've seen Flashback in a few cards across Lorwyn Eclipsed, Avatar, and Final Fantasy, it's always nice to see it front and center here