===========================================================================
The castle is divided into eastern and western wings. Every wing contains 
a statue head.

In order to acquire statue head in the eastern wing, you must find a 
semi-hidden switch in the cellar. Activating the switch opens polyobject 
doors in that cellar. You'll find the head at the end of the hallway.

Getting the head in the western wing is more complex. First, you must
acquire the dungeon key.

Acquiring the dungeon key: go to the eastern wing. There's a chimney in the
kitchen where a pig may pass. Go to the cellar and press a bull switch; a 
porkalator projectile appears nearby. Touch that projectile. Now run to the 
kitchen and go through chimney, you'll reach the roof. Wait before you morph
back into the human form and then search the square tower. The dungeon key 
can be found near the scorpio/ballista.

Exploring the dungeon: once you get rid of all monsters in the dungeon, you 
may find a room with odd yellow blocks. These blocks can be pushed (by 
bumping into them) to change position of platforms in the other part of the 
dungeon. The rest you can figure out yourself. 