It gets really challenging. Makes you ask the "What diabolical mind could..." question. After you though you made the most impossible and complicated ball, it throws an other one at you. Nice game.
Was this game sponsored by some eye-glasses company? If you want to make a challenging spot the difference game (which is a great thing) then please use more detailed pictures or pictures with more details. Looking for pixel-sized differences in a scene with only grass and sky isn't fun at all. It would be better to find small diferences on a big, close up portray with deep details for example (or a busy scene at a market not with still-lifes with 2-3 figures and blank backgrounds)
Brilliant game, but PLEASE do something about those darn fish! It is so frustrating. Not that it's very hard, but it's hard to tell how far you must stand from them as they kill you when hitting the air next to you.
 "Bela Kovacs and The Trail of Blood"){kind=icon}
 "Mana Chronicles"){kind=icon}
 "Interlocked"){kind=icon}
 "Neil the Nail"){kind=icon}
 "Fantasy University"){kind=icon}
 "Tesla Death Ray"){kind=icon}
 "Arkandian Crusade"){kind=icon}
 "Child of a Witch 3"){kind=icon}
 "The Witch Circle"){kind=icon}
 "Factory Balls, the Christmas edition"){kind=icon}
 "A Mage's Day"){kind=icon}
 "Papa's Burgeria"){kind=icon}
 "Doodle Devil"){kind=icon}
 "Lucky Tower"){kind=icon}
 "William and Sly"){kind=icon}
 "Belial Chapter 2"){kind=icon}
 "Wizard's Run"){kind=icon}