Keen 6 Bugs

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This page lists all the bugs, odd behaviours, unexpected actions and mistakes (such as typographical errors) that have been discovered in Keen 6.

Level bug: The Bloogdome – Walk into the rock

The Bloogdome "walk into the rock" bug

In the top left corner of the Bloogdome, it is possible to jump through the rock surrounding the dome and run around inside the grey rock surrounding the level.

Steps to reproduce:

  1. Go as high as you can in the level, until you can see the grey rock.
  2. Go across to the left, until the grey rock starts to appear at the left of the level as well.
  3. In the angled section of rock closest to the top of the level (as soon as it angles down towards the left) there is no blocking, so you can jump across into the rock (or pogo up from the lower ledge just below.)


Typo entering Bloogfoods, Inc.

Typo in the word "hungrily"

When entering the Bloogfoods, Inc. level, the entrance text reads "hungily" instead of "hungrily".

Steps to reproduce:

  1. Enter the level, observe the message on-screen; it says "hungily".

The v1.5 patch fixed this bug.


Typo entering Bloogbase Recreational District

Typo in the word "Bloogbase"

When entering the Bloogbase Recreational District, the level text reads "Bloogbae" instead of "Bloogbase."

Steps to reproduce:

  1. Enter the level, observe the message on-screen says "Bloogbae"
  2. Press Enter while in the level, observe the level name begins with "Bloogbase"


Impossible Bullet

Impossible bullet.

This bug requires careful timing to exploit, and only works in Keen 6. It is not an officially documented trick as with the Impossible Pogo Trick, but named as such by fans upon its discovery due to its comparable difficulty and niftiness. The trick allows the player to fly upwards, until hitting the ceiling or otherwise interrupting the manoeuvre (such as by jumping — although it is possible to walk a couple of pixels left and right before "falling off" the bullet). It can be very helpful in levels such as Bloogton Tower and getting the Grappling Hook in the First Dome of Darkness, although technically it is considered cheating.

Steps to reproduce:

  1. Jump in the air.
  2. As you start to fall, shoot downward.
  3. If done correctly, when you land, you should be standing a tile above the ground.
  4. Shoot up, and you will fly up with your bullet.

It takes some practice to get the timing right.

If you are standing against a wall when you perform this trick, shooting into the wall will also raise you by a small amount. The Impossible Bullet bug is used extensively in a walkthrough for Keen 6 in which the player gets no points, exploits various clipping errors, etc. Commander Keendom, the website that originally provided the walkthrough, is now gone but there is a copy of the walkthrough rescued from www.archive.org.

The technicalities of how this trick works are at least partly unknown, as the source code for the games has not been made available. The mechanics seem to revolve around the fact that Keen's collision code allows him to interact with shots reflected back by the Flect. The code is missing a break, which means that the code following it is also run. This deals with Keen's collision with moving platforms, allowing him to stand on them. As such Keen can stand on any of his shots in the game. The only time this can happen however is if he is right above a shot that has stopped moving. This happens when a shot hits a floor but before it changes its sprite type to be a "zapped" bullet, and Keen is falling onto it.

Once standing on the shot Keen's position is "slaved" to it. This is done by storing a variable whose value is the "sprite slot" that Keen's position is linked to. Ordinarily he will remain "riding" the platform until his hitbox no longer overlaps horizontally with it. (If he walks or is pushed off of it), but Keen's shot in this case "zaps" and is removed from the game. When this happens the sprite slot is simply not updated anymore, but the data it contains, including its position, is not nullified. As such Keen can continue to refer to it and the game is unaware that he is not standing on anything.

When a new sprite is created in the game it uses the lowest available sprite slot to store its data. In the case of the impossible bullet, when the game next refers to the slot it thinks Keen is standing on it will find updated properties. Most often this will make the game think Keen has moved off the "platform" he was standing on, causing him to fall down and regular gameplay to resume. However if the new sprite is of the right type (that is, one Keen can stand on) and its hitbox still overlaps Keen's horizontally, then the game will think Keen is still riding the "platform" and will adjust his vertical position to match it.

When Keen shoots upwards his shot matches these criteria. Once he has been warped to stand on top of it, regular platform rules allow him to ride it up until he's knocked off by a ceiling, walks off sideways or presses jump and down. If Keen is standing next to a wall and shoots then his shot will be pushed back by wall clipping enough for him to be considered to still be riding a platform. However the shot quickly changes type as it "zaps" so Keen can't ride it. The game is only able to warp him a short distance, causing a small vertical jump.

See also: Impossible Bullet Trick


Eye am stuck

Stuck Orbatrix.

In many levels, if the Orbatrix are bounding about, then unfurl next to a sloped surface, or even a wall, they will become stuck in the ground and just hover up and down. They may be freed if Keen walks close to them, causing them to furl and bounce again. It is harder to trap an Orbatrix in a wall, but it can be done. The trick is to pay attention to the bounce width, Orbatrix will stop at the bottom and end of a bounce. You should "activate" the Orbatrix about 4 tiles away from where you want it to be trapped. This trick is easy once mastered and a great way of detaining an indestructible enemy.

Steps to reproduce:

  1. Go somewhere, like near Molly or in BASA, that has both Orbatrix and sloping surfaces/walls.
  2. Make the Orbatrix curl and bound, you will need to do this carefully to avoid death.
  3. If properly positioned they will unfurl and get stuck.


A nose for trouble

Nospike stuck in walls.

If a charging Nospike rams into a wall, it can get stuck in it, either walking back and forth rapidly on air, or standing 8 pixels higher than normal in the wall. It cannot charge, unless shot. When shot, it will charge, pause, then fall 8 pixels to the floor and stun as if it had fallen off a cliff.

Steps to reproduce:

  1. Hard mode is helpful.
  2. Go to the Bloogdome.
  3. Try and make a Nospike charge you as much as possible (God mode helps.)
  4. If done right, some will get stuck in walls.


Molly's escape

Molly escapes from her prison cell.

Only in version 1.4 Molly jiggles out past the doors to the right. This glitch happens because of changes in the properties of Molly's sprite. She is being positioned too low and this makes her slide out of her cage. This means that the player does not need to collect the Keygems because Molly will waltz right over to Keen. Eventually this bug has been fixed in version 1.5 so that Molly is correctly positioned.


Rhetorical Question

A Nospike all confused.

If you manage to reproduce the above error, under the right circumstances, you may be able to preserve the Nospike's question-mark of surprise. This bug has to do with sprite/tile collision and means it will only occur if the question can be made to appear in a tile that blocks from the sides or bottom. It is almost impossible to get this glitch to work, especially without cheating.


Eyeball confuses camera

If you stand on an eyeball and save your game, when you load the game again the camera becomes broken and shows the wrong part of the level (not where Keen is). There is a video demonstrating this at YouTube.


Blorb stuck in a platform

If you flip a switch that activates a platform while a Blorb is in the platform's area, it will become stuck once the platform is deactivated. Depending on its position, it may kill Keen. It will also make a lot of noises.


Stand-a-Switch

Standing on the switch :).

In the Bloogton Tower, you can stand on the tall switch without flipping it. Simply ride the Goplat to the left of the switch, while the platform is going down, go the far right of the platform and wait. You will be standing on the edge of the switch.

Steps to reproduce:

  1. Activate the platform.
  2. Make sure the switch is in the up position.
  3. Wait for the platform to get to the top.
  4. Go to the far right of the platform.
  5. Wait till you pass the switch. If done correctly, you will stay on the switch.


Jump Through Walls

Jumping through the wall.

In Bloogfoods, Inc., some of the vertical walls of the downward snaking passage can be jumped through. If the other side has nothing above it Keen can freely clip through it without any sort of cheats. This exploit allows the level to be completed without ever retrieving the green key.

Steps to reproduce:

  1. Go to Bloogfoods, Inc. past the red and blue doors
  2. Stand against the vertical wall
  3. Jump while walking into it
  4. Some times Keen will not pass through and instead rapidly look left and right until a key is pressed


Offscreen onscreen

Keen offscreen

There are several levels, notably the BWB Megarocket, where Keen can go offscreen. If he saves his game in this position, when restored, you can see the level's edge.


Unobtainable extra lives and candy

Unobtainable extra lives and candy, highlighted with patches.

In Bloog Aeronautics and Space Administration, there are two Queen Vivas and one Pudding hidden in the floor at the bottom of the level between two retractable bridges. These items are unobtainable without cheating.


Clipping bug with Bipship

If a Bipship is blocked as seen in the image and you shoot it, it gets moved through the wall together with the Bip to the right (probably a clipping bug), resulting in the Bipship trash lying and the Bip standing in the air (seen in the second image). Additionally, you can stomp this Bip from below.


Flags clipping in front of Scorebox

The Flag appears in front of the Scorebox.

Both the flipping and sitting Flags use a foreground variable of 3, putting them in front of all tiles at all times. Sometimes this can cause issues for eg. on the Worldmap when the Flags will appear in front of the scorebox. This is because the scorebox has the same foreground behavior to ensure it appears over all tiles. The scorebox is nearly always spawned first, putting it higher up the foreground list, meaning a sprite 'equal' to it will appear in front.