To unlock the "Challenger" trophy in The Bridge you need to complete the six levels of Chapter IV. You'll find Chapter IV in the basement of the game's house.
To get to Chapter IV use the Inversion point that has appeared in the bottom of the House after completing Chapters II and III.
This next chapter introduces a Veil. When the Professor is behind the Veil the level can be rotated without affecting the Professor -- he will only move if you prompt him, even if the level is turned upside down (if he is sliding when he enters the Veil he will continue to slide along the same surface until he exits the Veil again, regardless of any rotation you cause). There's also a "wind" of sorts which will make certain black-tinged objects (Menaces, keys) "fall" in the direction of the wind rather than the direction of your rotations. Both elements combined mean that you can significantly affect the level's movable objects while not moving the Professor, which is key to completing the levels.
Chapter IV-I: The VeilFirstly pull RT to tilt the wind-affected Key so that it falls up into the alcove directly left of its starting position. Now walk (with a little LT rotation to help you) to the shower-curtain thing in the left corner. This is the Veil. Once inside, rotate with LT all the way until the key falls down near the door (pull a little with RT if it's threatening to fall off the edge). Now walk back around (with a little RT pull to help you), grab the key and exit.
Chapter IV-II: The RookDon't walk anywhere. Rotate firmly but carefully with RT and the Menace will continue to roll just ahead of the Professor. Stop when the Menace is covering the door. Enter the veil and rotate with RT again, so that the Menace is opposite the door. Walk right out of the veil and continue to the door, rotating with RT when necessary.
Chapter IV-III: The BendRotate with LT and walk to reach the Veil. While in the veil, move the Menace through the S-bend so that it's on the button. Now keep rotating the level with LT (still from inside the veil) so that the Menace comes off the button. Make sure you don't move so fast that the Menace escapes the button-end of the S-bend. You want the Professor, frozen behind the veil, to have his feet point towards the top right corner (towards the button) and his head point directly towards the wind-affected lantern. This ensures that the Menace will be headed back to the button at the right time once you exit the veil. Exit the veil and by the time you walk/rotate the Professor back to the door, the Menace should be back on the button.
Chapter IV-IV: The TriadThe Inversion points in this level are small and difficult to describe; luckily you'll always be going to use the nearest Inversion. Walk right and pull RT and use the first Inversion you see. As White, walk left and use the first Inversion point but keep an eye on the Menace on the far side of the portal -- you want to make sure it's not going to immediately crush Black. Once through, send Black into the Veil and turn the level upside down (180 degrees). Head out left and pull LT so you can get to the next Inversion point, quickly so that the rolling Menace doesn't get you. As White, walk left and again use the next nearest Inversion. As Black you should now be able to pick up the black key.
Head left as Black and use the next nearest Inversion (again check that the Menace isn't too near the other end of the Inversion). As White, walk to the Veil and flip the level 180 degrees again. Now just keep heading left/pulling LT and use the first Inversion you see each time; eventually you will reach the unlocked door as White.
Chapter IV-V: The IntersectionThis next chapter is complicated particularly if you are going for the Slider trophy, which is described below. You might as well get it now.
Do not press the left analog stick at all during this level to get the Slider trophy. You must not allow the Professor to walk manually, he must only slide.
Unless otherwise stated, you only need to press RT during this entire level.
SetupStart off by getting the Professor into the corridor with the door by slowly pulling RT. Next you need to get the Professor near to the Vortex button (there's a Vortex symbol next to the button) but you also need to get the Menace into the Vortex before the Professor reaches the button. Pull RT slowly to achieve both of these events at once (rotate too fast and the Menace will skip straight past the Vortex and onto the key button, which we don't want.) Rotate a little more with RT to get the Professor onto the button -- the Menace needs to end up by the exit door. Keep rotating, faster this time, to put the Professor into the Vortex, then rotate further to get the Menace onto the Vortex button and free the Professor. Tweak the Professor left with LT so that he's resting in the corner at the bottom (incidentally, tweak LT around until the Professor is touching the Lantern to get a Wisp towards the
Collector trophy).
Repeat the next stepsWe're going to slowly spin the level for roughly five or six minutes now in order to change the distance between the Menace and the Professor. The end goal is to get Menace to be on the Vortex button while the Professor is falling through the Vortex-free space, so that he can end up by the door while the Menace is by the Vortex button. In order to close the gap between the two, we're going to hold down RT firmly only while the Professor is sliding behind the veil, allowing the level and Menace to spin further while the Professor retains the same speed and direction.
Here's how we do it.
1. Rotate with RT slowly so that Menace goes to the door.
2. Now rotate RT a little more firmly to shoot the Professor off towards the Key button at the bottom of the screen, rather than into the Vortex.
3. Rotate slowly with RT to start the Professor's slide towards the Veil while Menace heads to the Vortex button. Ideally you want to be going
as slow as possible to allow the Professor to be behind the Veil as long as possible, however you need to make sure that Menace doesn't ricochet off the button and into the Vortex. For the first few rounds you will be at a steeper incline, as time goes on you should be able to put the Professor on a slower slide to the Veil.
4. While the Professor is behind the veil,
pull sharply on RT so that the level rotates further while the Professor maintains his course and speed. The Professor will end up back in the bottom corner.
5. Repeat steps 1-4.
Gradually you will start to notice that Menace will leave the Vortex button earlier and earlier in the rotation as you repeat these steps. You want to repeat them until you think that you can have Menace pressing the Vortex button down at the same time that the Professor is falling towards the Vortex area (Step 2 above). That way you can divert the Professor safely to the door while the Vortex button is down.
Try and achieve this position with as few repeats of the above steps as possible so that you don't overshoot.
Completing the levelOnce you have the Professor at the door, rotate with RT to put Menace back in the Vortex and the Professor on the Vortex button (so that Menace ends up in the corner opposite). Rotate slowly to put the Professor back by the door. Now pull firmly on RT to put Menace at the key button, allowing the Professor to exit.
This may take a few tries. If you think you have touched the left stick at any point
quit out of the game entirely and try again; the game is a little glitchy about unlocking trophies on a second attempt if you haven't completely quit out of the game between attempts.
Here's a video to illustrate the process above from
Radiotelegrafist. All credit to him for the video. I strongly recommend that you watch the video and read the above instructions -- I don't think you get a full understanding without both aspects.
Once you finish the level you should earn the following:
The Slider trophy in The Bridge worth 35 pointsComplete The Intersection without walking.Pay attention to the orientation of the arch which is at the top of the level when you start. First rotate with LT and head through the first Inversion point you cross (the Arch will be pointing South). As White, walk all the way to the Veil, past its bottom edge, past the door and past the top edge of the Veil, so that you're standing on the inside edge of the southern pillar of the archway (The Arch is now pointing West). You now need to shift RT just enough that Menace rolls into the corner underneath the northern pillar of the Arch (if you imagine the original configuration of the level, Menace is now in the top-right corner). Don't rotate too much as White needs to be able to walk uphill back to the Veil. Get in the Veil from the nearest edge and rotate with RT so that the middle, Wind-affected panel slides all the way from the bottom section of the level to the side with Menace (Menace will stay locked in place while you're in the Veil). Walk right out of the Veil and keep going all the way across the panel you just moved, so that you're behind the Menace (which will start to roll away).
Keep following the Menace around and it'll eventually get trapped by the panel, which will have slid back to the button side of the level. Menace will likely be trapped on the wrong side of the panel, away from the button -- we need to get Menace trapped by the panel in the Button quarter of the level. Rotate around so that the Arch is facing towards the West again. (White should be in the bottom left corner, Menace in the middle of the level). Tweak with RT so that the panel slides back towards the top of the level, but White doesn't slide too far towards the button. As soon as the panel is clear of Menace, pull back with LT to thrust Menace into the Button corner of the level and bring the panel back down to the southern side, effectively trapping Menace with the button with White still on the other side of the panel. (Arch is pointing South). Walk left and use the Inversion. (Arch = facing North, Menace = near button, Panel = left side)
As Black, you need to walk right all the way around to the Veil. Get in from the nearest edge (Arch is pointing right). Now you'll need to pull RT to rotate the level 180 degrees so that the Arch is pointing left. However, you need to keep Menace in the Button corner of the level. You might have to pause or compensate with LT as the panel will slide around and Menace may roll back and forth a bit over the panel's edge. Only move with RT while Menace is on the Button-side of its roll across the middle. Gradually you will be able to reach an 180 degree turn and Menace will still be trapped near the button. Now just walk right and rotate as needed to walk all the way around (past the door, the Veil and further) until you eventually reach the next Inversion (the same Inversion you used with White last). Use that Inversion and as White walk all the way around to the right until you get to the door. Menace should be on the button at the same time allowing you to exit.
Video guide Courtesy of
MrMorton: