Q:

What is the hidden achievement in Little Alchemy? 

This new web game, Little Alchemy, has a hidden achievement.  Does anyone know how to get this achievement? 

Is This Just Fantasy? 
  A hidden gem, eh? 

https://littlealchemy.com

A:

According to the wikia page, you get this achievement for crafting one of the nine hidden gems. 

There are 9 hidden gems in Little Alchemy.  Creating one will get you the achievement "Is This Just Fantasy?" 

The gems you can craft to get this achievement are:

Astronaut Ice Cream (astronaut + ice cream)
The Doctor (tardis + doctor)
Tardis (space + time)
Doge (dog + computer)
Keyboard Cat (cat + music)
Ninja Turtle (ninja + turtle)
The One Ring (ring + volcano)
Yeti (mountain + story OR mountain range + story)
Nessie (story + lake)

(Combinations gotten from the wikia in conjunction with this site, as the wikia did not have Nessie)

