In the arcade game Tempest, players controlled a blaster that could move around the outermost lanes of a bunch of geometrically-shaped levels and fire at ships that emerged from the middle or innermost areas of those levels.
Bedlam, however, was a "Tempest in reverse", where players' ships (resembling the Millennium Falcon from several of the Star Wars movies) sat in the middle of sectors while ships emerge from points of those sectors and came inwards towards the player. Players turn their ships left and right and can spin them around quicker with the Fast Rotate button. Also, Zap, like the Superzapper on Tempest, will destroy everything on-screen and can only be used once per sector.
There are several different types and mannerisms of enemies as well as sectors. Getting rammed by an enemy will cause the player to lose a ship in reserve and the game will end once the player has no more remaining ships.
- Choose between starting levels 1-3--buttons two or three
- Choose number of players—button one
- Start game—button four
- Move ship—joystick or D-pad
- Fast rotate—buttons one or three
- Zap—button two
- Shoot—button four
Enemies, sectors and difficulty increases
- Escort Ships—heads straight for the player's ship without stopping
- Astral Defenders—comes to a stop when the player faces it
- Colonist Transports—cannot be destroyed with regular weapons due to its strong shields; can only be pushed back by being shot or can only be removed from the sector by using Zap
- Destroyer Droids—encircles, then heads straight for the player's ship when it's directly behind it if it gets close enough
- Sector 1: there are only three entry points for ships to emerge from, as this screen is shaped like a pyramid
- Sector 2: four entry points for ships to emerge from; shaped like a bird's foot
- Sector 3: six entry points on this one
- Sector 4: this signifies the start of a next level, having only two points of entry for enemy ships on this one, which the sectors will start recycling after this sector is passed
- Level 2: sector areas start collapsing; the player must shoot out the ends of a sector to keep ships at bay. If the player allows the entry points of a sector to get real close then enemy ships can emerge from these points and be right on top of the player's ship. This also marks the debut of the Destroyers
- Level 2, sector 2: Colony ships debut
- Level 3: sectors start rotating around
- Level 5: sector areas start pulsating (note: due to the areas filling up most of the space on the Vectrex' screen, this isn't really noticeable unless a two player game is played, since sectors start off in the background in between players' turns)
- Level 6: sector areas not only rotate, but start doing so at a high rate of speed as the player turns left or right, making it hard to get a shot in at anything
- Escort Ships 75
- Astral Defenders 100
- Destroyer Droids 150
- Colonist Transports 175
- Extra ship awarded at every 10,000 points
A lot of the time when Zap is used and there are a lot of ships onscreen, they will still be remaining afterwards. Staying still for a second or so and then using Zap remedies this problem most of the time.
- The Colony and Destroyer ships look pretty alike at first glance, which makes it difficult for the player in case a ship gets too close and it turns out to be a Destroyer, rather than a Colony ship.
- On the first level only, there is somewhat of a pause: if an Astral Defender is the last enemy remaining in a sector, the player can face them so they'll stop in their tracks, and there is no way for the player to die or for the game to be interrupted. This only works on sectors during level one though, since, once the sectors start moving on level 2 and onwards, they can move the enemy ships as well, disrupting the pause.
- Stage Select review (7/10)