Frankenturret

Frankenturret

The man himself!

Overview

Frankenturret (also known as prop_monster_box) is the homie of Chapter 8 and 9. It's a cube-and-turrets abomination Wheatley created in order to make test chambers solve themselves. How stupid of him. They have some interesting properties, which are useful for speedrunning and breaking the game in general.

Mechanics

States of frankenturret

Frankenturrets have two states: box state and monster state. Each of them have their own collision model, regular box for former and more detailed model with expanded legs for latter. There's also short circuit state which is basically box state from technical point of view.

The state is controlled in two ways:

• Through event inputs (BecomeShortcircuit, BecomeBox and BecomeMonster), mostly activated by triggers which are present near buttons, but also exist independently in some cases.
• If not forced into short circuit or a box, frankenturret can change itself into a box if its speed becomes higher than its switch speed (400ups by default) and becomes monster again if speed becomes smaller than the switch speed.

Interesting thing to note is that the second rule is ignored when you hold a frankenturret. Once you grab it, it will keep its previous state until you drop it and let it "update" its speed.

Fail-safe boost

There's a special fail-safe mechanism. If the game detects the possibility of the frankenturret getting stuck in a solid object because of a collision model change, it will apply some velocity upwards relative to the turret repeadetly until it can change the collision model safely. This has an interesting side effect, which will be explained in #Frankenturret Flying section.

Tricks and glitches

Finale 1 Double Cube Hop

When frankenturret drops from the cube dropper in Finale 1, a bunch of event calls are controlling its state. In result, it becomes a monster while its speed is above switch speed. This special state can be preserved by grabbing the cube before it slows down below the switch speed. This allows us to drop the frankenturret at high speed with its longer hitbox, which gives us an opportunity to jump from it midair, allowing us to hop over the Wheatley screen, saving a little bit of time in Challenge Mode run. More details about the route itself can be found here.

Frankenturret Flying

Because of the fail-safe mechanism explained in previous section, you can position the frankenturret next to a wall in a way so it will try to boost into said solid instead of away from it. It requires you to hold it with "high speed stored", then drop it close to the wall. This can be used to climb vertical walls, as one can stand on the frankenturret while it tries to push itself into a wall, effectively slowly shifting itself and the player upwards. The glitch is used mostly in a bunch of Least Portals routes.

Frankenturret Button Abuse

The same method explained above could be used to keep frankenturrets on ceiling buttons.

TODO: add more detailed description

Trivia

• In Test, one of frankenturrets you see from observation room is actually an animated dynamic model with completely messed up collision model. This creates a very unlikely softlock opportunity, where that dynamic model pushes regular frankenturret into the button, activating the panel blocking passage earlier, which leads to a dialogue opening this panel to be interrupted, effectively never unlocking the passage for a player and blocking them from proceeding futher.

References

TODO: add images and videos