I can see how they managed the former games by adding constraints that keep you away from vast landscape sights, but - in case this game actually runs with good fps - this makes me speechless.

http://www.puppenheim.org/
http://www.wuerfels-welt.de
Old Game Tutorial: http://www.puppenheim.org/MITutorial.zip
Free Game Editor: http://puppenheim.org/AlienalsWeihnachtsmann.zip
http://www.puppenheim.org/blender_starting_main_settings.txt