Hey i have clocked through the game twice now and i still can't find the last bloody easter egg.
I have the unlocked the followin g challenges
Maze
Stone knights
Defend the ring
kill all enemies

whats the One i'm missing? and where can you find the easter egg?

it's not the one by the telescope. but I don't know where it is, either

Depends on what you are after. The eggs are quite easy to find but consult a walkthrough if your having difficulty finding them.

The last challenge you are after is the blood bath challenge.

In dracula's castle level you will get to an area with a pool of blood and three surrounding chambers. In each chamber use the alt lightning gun to power up the node. Once all three are powered up, the pedestal will be raised out of the blood pool.