The Sentinel

At the highest vantage point stands The Sentinel, a statue-like being with an energy draining stare, you begin at the lowest. "Energy" plays an important role, there's a constant amount in the game world and each object is worth a certain number of units - including you.

The object of each level is to absorb The Sentinel and Hyperspace to the next from his vantage point.

The Sentinel scans further round the landscape every few seconds - if you're caught in his gaze, or rather the square you are standing on can be seen, you'll have about 5 seconds to teleport to another location (or hit a key to teleport to a random location - which will never be higher, and may be lower than your current level) before the Sentinel begins absorbing your energy, when it reaches zero you will be destroyed.

To travel a "robot hull" must be created on a visible square then teleported to, making sure you absorb your old hull to avoid losing energy.

Boulders and trees can also be created, trees to block The Sentinels view and boulders can be stacked to gain higher ground.

There are a few other elements to the game - on later levels there will be other Sentries positioned around the landscape.

If only part of you can be seen i.e. not the square you are standing on, a nearby tree can be changed into a "Meanie" which will ultimately force you to teleport.

There are 9999 levels in the game but the next level number is based on the current level + how much energy you have remaining.

The Sentinel for Commodore 64 is currently worth €9.63 loose, €48.22 complete in box, and €96.44 factory sealed. Prices are based on real sales and update regularly on Gamevaro.

The Sentinel has a steady sales history on the tracked marketplaces, meaning it trades hands regularly and isn't considered particularly rare.

Loose means cartridge or disc only, CIB (complete in box) includes the original box and manual, and sealed means factory-sealed and never opened. For The Sentinel, loose is €9.63 and CIB is €48.22 — CIB commands a premium because original boxes and manuals are fragile and often don't survive.