To defeat the demon-spitter in PC TNT level 30, Last Call:

THE BOSS
--------
As you first teleport into the large chamber at the east
side of the map, you'll be facing north, away from a giant
"demon-faced wall", the game's final "Boss".  Destroy it
and you win the game.
In the wall, in the demon's forehead, you'll see a small
rectangular hole.  From this hole the Boss will begin
launching an infinite number of small, skull-faced boxes.
Each box, at some point in its flight, will spontaneously
turn into a monster.
WARNING: If one of these flying boxes "spawns" a monster at
(or above) the player's current coordinates, the player is
destroyed.  This is true even if the player is "invincible"
through the use of power-ups or cheat codes.

BEFORE YOU ATTACK
-----------------
Activate the switch mounted on a vertical metallic slab,
which is located on a low platform just north of the center
of the room.
To get to the switch, begin walking up one of the curving
stairways on either side of the room.  As you walk up, step
up onto and over the low wall that runs along the side of
the stairway.
The switch will cause more stairs to emerge.  These lead up
to the high platform at the north end of the map.
Go up to the top of that high platform, and get your rocket
launcher ready.

THE TRICK
---------
Carefully take one step down from the top edge of the high
platform, and fire your rockets (or other projectiles)
south, towards a point just BELOW the visible rectangular
hole in the demon-faced wall.  One end of an invisible tube
is located beneath the visible hole in the wall, and leads
south to a vulernable area beyond.
While the Boss can be killed with one well-placed rocket,
fire 2 or 3 down the tube just to be sure.

To access a demo of this level which shows the method used
to kill the demon-spitter, click here.

Good luck!

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