Frenzy was an old arcade game released by Stern way back in 1982.
Berzerk was Stern's first real big hit, and Frenzy was the sequel. Frenzy expanded on the original Berzerk formula by adding more varied opponents, and different types of walls. This was one of Stern's last games, so the production run was rather limited.
Frenzy consists of many levels, which are each a little maze of rooms, populated by robotic skeletons, robotic octopi and walls. Everything is deadly, touching anything (wall, robot, laser shot, your own shot, Evil Otto, etc) will kill you. The object is to shoot all the robots, and then escape out of the room through one of the doorways. You must be quick in your mission, or else Evil Otto will appear (he is a big bouncing happy face, that kills everything that moves). He will move relentlessly towards you, speeding up after all the robots are killed. You can kill Evil Otto with four shots, but then he will reappear moving faster than before (if you manage to evade him for a long time, then he will be joined by a second Evil Otto).
The robots live by the same set of rules that you do. They will also die if they touch anything at all, including a wall, another robot, Evil Otto, or a blast from your weapon (or even another robot's weapon). You can use this to your advantage by tricking them into shooting each other (you still get the points anyway). They are however a lot smarter than the robots from Berzerk, and will try and dodge your shots, and don't blunder into walls nearly as often. A good player can even manage to make Evil Otto smash the last few robots for him.
Most of the walls cab be shot away one brick at a time, this allows you to make your own exits, or hit robots that are hiding behind them, but beware, because the robots can shoot through them as well. Other walls reflect your laser blasts, allowing you to bank shots, and pull off other tricks. Some of the higher levels are composed mostly of these reflective walls, try to run out of the way, and watch the robots blast each other with bounced shots.
Some rooms have machinery inside of them, shooting the machine will either cause some of the robots to vanish, or cause all of them to stop moving. There may have been other possible effects, but the machinery levels are few and far between (and this game is very difficult, so it is not like I can just go checking every level).
You get bonus points if you manage to kill all the robots on the level. This is simple at first, but the game quickly ramps up in difficulty to the point where you are simply trying to shoot a path to the exit (before Evil Otto shows up). It takes a very skilled player to consistently kill all the robots on the higher levels (I certainly can't do it).
Frenzy speaks to you as you play (many of the samples were copied over from Berzerk). It has a voice synthesizer that spouts lots of little phrases like "Stop the Humanoid", "Stop the Intruder", "Intruder Alert", "Chicken! Fight like a Robot", and "The humanoid must not escape". These were done in a monotone computer voice, which was difficult to understand when combined with other in-game sounds. (The voices were actually done using LPC encoding, which cost $1000 per word back in 1980). These phrases were also translated into several European languages (Spanish, French, and German) for release in Europe.
Good luck in your attempt to defeat this game. It has 64,000 levels, at the end of which the game will crash. Not that anyone has ever made it that far in real life.
The Frenzy cabinet had a patented pull out drawer that allowed access to the games circuit boards from the front of the cabinet. (This makes an old Frenzy cabinet excellent for use as a JAMMA cabinet.
Frenzy machines are bright orange, and are not (IMHO), as cool looking as Berzerk machines were. The graphics are mostly done in blue, yellow, and orange, and are just simple designs for the most part.
This is technically a monochrome game. It uses a special "color overlay" circuit board to add color to the games graphics before they go to the monitor. A side effect of this is that walking very close to a wall, robot, laser blast, etc, will cause part of that object to change to your color.
This title uses a Z80 processor, and the CPU board is a direct plug in for the game Berzerk (the rest of the boards in the set are identical).
Where to play
Frenzy is going to be a little to add to your arcade game collection. It is very hard to find, because of its low production numbers. Luckily it is usually cheaper than Berzerk, and provides similar gameplay.
If you can't locate an actual arcade game then try playing the Atari 2600 version, or using the MAME emulator. The MAME version has a few problems. Some of the sound effects seem to be missing, and the robots do not speak nearly as much as they did on a real machine (it is quite playable, it only seems different when compared to a real machine).