Like most Magic: The Gathering cards, the value of Liberator, Urza's Battlethopter depends on a few consistent factors: its rarity, the printing and finish (regular or foil), its physical condition, and the set it was printed in (The Brothers' War)
Its play on "ambush," complete with the surprisingly cutesy stylized ogre, is unexpectedly enjoyable
But instead of being creepy, this Feebas card from Crimson Invasion looked like it seemed something surprising that its reaction is clearly a meme-worthy one
You either create cards that just objectively suck (i.e.: most of this list), or you risk making an actual good leyline that breaks the game by nature of how these cards work
Do some mana fixing by copying Urborg, Tomb of Yawgmoth or commander protection by copying Karakas as long as either of them are in a graveyard