This almost-landfall ability can also tap down opposing non-lands, which is nice added functionality, though being a creature makes it more vulnerable to removal
Those are way too good, but hopefully not good enough to be considered a mistake like the true fetch lands are considered
5 mana is still a lot to ask for the privilege of playing a second copy of Cabal Coffers in your deck, especially when you have to wait a turn in order to use it, but the amount of mana you can get if it survives will fuel some very explosive spells and turns
If its an artifact, creature, or land card, you may put it onto the battlefield with a manifestation counter on it
Whether its a big X spell like Crackle with Power or Forth Eorlingas, a bevy of ordinarily expensive artifacts like Wurmcoil Engine and Darksteel Reactor, or just suiting Sami up with spendy Voltron Equipment