This demo picks up where L8WTAce leaves off -- outside the red door, ready to engage the boss.
Inside the boss's lair, there are many preparatory tasks that must be completed before dispatching the boss. There is a fairly loud welcoming committee, fueled by several strategically placed robot generators.
Also behind the red door is access to the shaft visible from the room just below the starting point.
And then, of course, there is the matter of the hostages. They are protected by force fields, but fortunately, the switch to remove them is nearby.
As far as the boss is concerned, there are ample cloaks, invulnerabilities, and heavy ordnance (read Megas :-) behind the red door to allow you to eliminate him without taking too much damage. Some of these items are protected by force fields, so getting to them takes some doing.