For your consideration is one used, tested and working reproduction of Hard Head prototype game cartridge.   This is a prototype game that was never completely finished, there are bugs/glitches in the programming code.
 
The backstory of Hard Head (from Atari Protos)…
 
“In Hard Head you control a little Space Invader guy who must use the blocks at the bottom of the screen to build a tower and escape.  As the blocks come rolling down the conveyor belt, you must jump up and bump them so they land somewhere on the screen (the blocks don't count if they go off the edge of the screen).  The movement scheme in this prototype is a bit unusual as the longer you hold the joystick in a direction, the faster your little guy will run.  Although this is very realistic, it is a bit odd for a 2600 game and may take some time to get used to.  Once you have constructed a nice little tower, you must carefully jump on the conveyor belt and them climb the tower.  Be extra careful on the conveyor belt, as touching the blocks will cause your little guy to be flattened.  
 
Unlike most Activision games, Hard Head has no game variations. However since this is still a WIP, game variations may have been planned later on. The left difficulty switch controls the game difficulty (A=Easy, B=Hard), while the right switch appears to control how your character climbs the blocks. When the right difficulty switch is in the 'B' position you cannot touch the center of the tower, as doing so will result in a block smashing your character. Instead you must build the tower in a staircase-like fashion and climb up the edges of the blocks. Naturally this is much more difficult to set up than a simple tower of blocks, so this variation is recommended for experts only. When the right switch is in the 'A' position, your character can climb up the center of the blocks making things much easier. Although this prototype appears to be nearly complete, there are still a few bugs in the game. Glitches include such things as your character getting stuck in the walls, and the screen becoming unstable when being bumped by the yellow block or when avoiding the leg alien.
 
The graphics and sounds for this title are top notch; it's obvious that a lot of work went into this game. Everything from the smooth animation of your character to the cute "Can-Can" sequence at the start of the game screams quality. So why was this game never released? Unfortunately no one but the programmer knows the answer to this, but one possibility is that they may have left Activision before the game was completed.”
 
 
Refund Policy…
 
If I say it works, then it has to work.  My guarantee.  A full refund will be given after the return of the item and confirmation that it is nonfunctional, and no components were “swapped”.  
 
Shipping...
 
Domestic shipping choose between USPS Priority Mail or USPS Ground Advantage.  I reuse and repurpose boxes and packaging materials whenever possible.  This will be shipped in a box.
 
 
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