Never assume, and you’ll never be wrong. Works 100% of the time, guaranteed.
 
It’s all right anyways. I did sound a little bit over-tempo happy there and kind of tacked on the “But here’s the one use for it” as a sort of afterthought.

@Marioland  
Ah. Sorry, for some reason I thought you were prioritizing tempo over everything else. My apologies, I made rash assumptions, and you know what they say about assumptions. :P

@Background Pony #7175  

 
Alright, let’s sum up that PS. What does it mean in a nutshell?
 
 
“Even in the late game, it’s still anti-tempo, but it’s good card draw for combo pieces and option hunting”
 
Just how is that debatable or need numbers to back it up? Even you said “For many, getting more options late game is worth comprising tempo”, which is exactly what I said with different wording. We’re in agreement for gosh sakes, but I’m debatable for… just what exactly? Saying a 5 mana 3/3 doesn’t contribute much to the board for the mana cost? I’d think that was self-evident.
 
I don’t know how you can get a playstyle out of that either.

@Background Pony #7175  
This was me, BTW.

@Marioland  
Very debatable, your PS, and seems to reflect your play style more than anything concrete numberwise. For many, getting more options late game is worth comprising tempo because you are relatively secure and are more concerned with drawing a killing blow, whereas early game bad tempo can kill you. Can’t argue with anything else you said, though.

Not sure I’d run it in Miracle tbh. Sure, it’s a lot of card draw, but why pay 5 mana for 3 cards and a 3/3 when you can instead draw a nearly unlimited amount of cards for 6 mana and get +1 / +1 to boot? Gadgetzan Auctioneer will just about always be better in Miracle simply because it has unlimited card draw potential when added to the Rogue’s natural arsenal of cheap spells.
 
Sadly (or fortunately if you really hate Miracle Rogue), the loss of Conceal when the Year of the Mammoth rotates it into the Hall of Fame set will make it a lot harder for Miracle to subsist, since you can’t just Conceal your Gadgetzan Auctioneer and wallop your opponent once your mana has reset back to 10 next turn.
 
PS: Even in the late game, it’s still terrible for Tempo. It’s still just a 5 mana 3/3 on the board even without the mana crystal drawback, after all, and spending that much mana on a weak body is completely anti-tempo. It just nets you more options, and with that, possibilities for more value or more chances to grab your winning combo. the latter situation is where I’d expect it the most, trying to snatch up your combo pieces as fast as possible knowing you’ll win with it even if you slip on the board a little.

Is miracle still a thing? Cause this would slot in nicely. Other than that, this is a card that goes from kind of bad on tempo to AMAZING in late game match ups.

An interesting idea, but it will absolutely ruin your tempo. A 3/3 is a really small body, especially for turn 5, and giving your opponent a mana crystal only allows them to take off quicker unless they’re already at 9 or 10 mana.
 
That’s a heck of a lot of draw though, so it might be useful for combo-based decks as a lategame cycle if you have other means of controlling the board.