Terrible Lizards Chapter 4 Walkthrough: The Deep

Chapter 4 is the shortest main chapter in Terrible Lizards, but it has the most moving parts. The Deep takes everything you learned in the first three chapters and stacks it into one rescue: find DJ, recover his Allosaurus tooth, restore the camp's special lights, blow open Cavern B, climb the spire for the Crew Lift Key, and survive Dennis long enough to reach the surface.

The chapter is generous with checkpoints and stingy with direction. Most of the confusion comes from the camp layout, where Cavern A, Cavern B, and the crew lift all connect through the same set of paths. The route below follows the order that keeps the backtracking short and gets the stuffed animal to its pedestal before the final chase.

Chapter 4 at a glance

The chapter's structure is a loop, not a straight line. You will pass through the expedition camp several times, and each pass opens a new objective. If you feel lost, return to the camp and talk to DJ. His dialogue is the game's way of pointing you at the next location.

Opening cavern and the counterweight

You begin in the strange underground environment reached at the end of Chapter 3. The walls are covered in glowing material, and the route is more organic than the industrial caverns above. Follow the open passages until you reach an abandoned expedition area with scientific equipment and a path leading upward.

The area contains several research records and a projector documenting Project Pilgrim. The projector is worth watching once. It explains why the expedition was down here and what the black material is, and it sets up the final reveal about Dennis.

The way out is above the current floor. Look for climbable structures and adhesive goo leading toward the upper tunnel. Part of this section requires lowering a goo surface with a counterweight before you can bounce to the next ledge.

When you reach a gap with the launch surface suspended out of reach, descend to the nearby control instead of trying to cross directly. Press the counterweight button. The goo moves into position, and you can jump onto it and bounce to the raised platform. Watch where the goo settles before you jump; approaching from the wrong angle sends you back to the lower floor.

Beyond the counterweight, continue along the adhesive walls, narrow supports, and elevated rock passages. You will pass abandoned military equipment, including old firearms. You do not need to collect them yet. The route continues toward the sound of a child crying.

Finding DJ and the Allosaurus tooth

DJ is alive, camped in a small shelter with a projector and a bed. He will not leave without an Allosaurus tooth fossil that he and his mother found together. Dennis took it to his lair, so Jordan has to retrieve it before they can attempt an escape.

Leave DJ at the camp and follow the passage into the nearby area filled with objects Dennis has collected. The lair is a hoard of stolen belongings: toys, equipment, bones, and junk. Search the collection rather than treating the first firearm or unrelated object as your goal. The tooth is the distinctive fossil among Dennis's possessions.

Pick up the tooth and prepare for a hostile encounter. Dennis does not let Jordan walk back through the lair.

The three guns

The escape leads into an area with three old guns. The objective changes to finding a working firearm among them. Their appearance is not a reliable clue, so interact with each gun rather than comparing models.

If a gun fails to fire, move to the next one. Once you find a working firearm, use it during the Dennis encounter to complete the objective and open the way back to DJ. This is a specific escape encounter, not a new combat system. Do not search for ammunition or try to carry an arsenal into the next area.

After the encounter, use the available control to open the return route and head back to DJ. Give him the tooth. He is finally ready to leave, but Dennis appears again before the pair can escape. Run along the collapsing route and follow the jumps and openings. Some terrain changes during the pursuit, so keep moving when a platform gives way.

The chase ends in another section of the underground expedition, where you can continue toward the crew lift and its surrounding camp.

The special-spectrum lights

At the expedition camp, Jordan learns that the crew lift needs a key. DJ is nearby, and Dennis remains a threat. Before you can safely investigate the camp, you need to restore its special-spectrum lighting system.

An expedition record explains why the lights matter: the underground material avoids a particular spectrum of light. Ordinary illumination is not enough. The camp uses filtered lights specifically intended to repel the creatures.

When Dennis approaches, leave DJ in the sheltered area and start restoring the system.

The three auxiliary switches

The main spectrum-light switch will not work while the connected power controls are inactive. There are three auxiliary switches to activate around the camp. They are distributed across the accessible structures rather than grouped together, and some require using the surrounding platforms to reach.

Treat the sequence as a series of short movements:

1. Identify the next switch and the route to it before leaving your current position.
2. Move to the control and interact.
3. Watch for confirmation that the switch has activated.
4. Continue to the next structure instead of returning to the main console after every interaction.
5. When all three are running, return to the main spectrum-light switch.

Dennis can interrupt the search. The camp has multiple routes around the structures, so use the openings to avoid running directly into him. A switch may look ready even though another part of the system is still unpowered. If an interaction does not finish the objective, check the remaining auxiliary switches before assuming the main console is broken.

Turning on the main lights

After the auxiliary sequence, operate the main special-spectrum lighting control. The activated lights repel Dennis and let Jordan return to DJ without the immediate threat that interrupted the search.

The change is visible in the environment: the creature reacts to the illumination, and the encounter ends. Do not assume Dennis is gone for good. The lights solve the camp encounter; later parts of the chapter still contain additional appearances.

Return to DJ and continue the conversation. He explains what is preventing the lift from operating: the Crew Lift Key is missing.

Cavern A, dynamite, and the blocked entrance

A recording explains that the expedition leadership deliberately separated the key from the lift during the emergency. One member took it into Cavern B, hoping to keep the creatures from reaching the surface. Jordan has to find that person and recover the key.

DJ stays at the camp while you search. You do not need to escort him through Cavern A or Cavern B, and there is no reason to keep returning to check on him.

Start by leaving the lift area and following the signs toward Cavern B. The entrance is blocked by an obstruction that requires explosives. Trying to reach the key directly does not work. The correct next destination is Cavern A, where the dynamite is stored.

The notice beside Cavern B says the dynamite is at the back of Cavern A. Enter Cavern A and work toward the back of the cavern, following the climbing route until you reach the explosives storage area. The journey involves more goo jumps, narrow rock passages, and elevated supports. There is no new movement ability to unlock here; use the bouncing and wall-running techniques you already learned.

Pick up the charge and follow the signs back to Cavern B. At the obstruction, place the dynamite at the marked point and trigger the blast. Wait for the way forward to open, then enter.

Cavern B and the spire climb

The entrance blast opens a long route through older expedition structures and unstable rock formations. The Crew Lift Key is not immediately inside the doorway. You have to progress toward a high spire and use the parkour surfaces to reach its upper levels.

Beyond the entrance, the route climbs through rock ledges, broken scaffolding, goo-covered surfaces, and suspended supports. Some platforms are unstable, so aim for the next support before committing to a jump. A visible walkway is not always a place where you can stop safely.

When you cross the suspended sections, use the bars and bounce surfaces instead of trying to cover the entire gap with one ordinary jump. The terrain becomes more vertical as you approach the spire.

Climbing the spire

Follow the upward route around the central rock formation. Look for the next illuminated structure, adhesive surface, or goo launch point whenever the apparent path ends. Several jumps require catching a hanging support or landing on a narrow ledge. Jump from a position where the intended support is already in front of you rather than trying to turn sharply in midair.

Near the top, the route reaches the remains of a former expedition member. Find the body and belongings, and collect the Crew Lift Key. A final note nearby explains how the member ended up here, but the key is the item you need for progression.

After you take the key, the objective changes to returning to the lift. You are not finished with Cavern B, however. Dennis interrupts the return trip, and the route back contains another obstacle.

The Dennis chase and the second charge

Dennis appears as you leave the spire. The climb becomes a fast escape. Follow the illuminated openings and bounce surfaces through the cavern while the creature pursues you. Some lights along the path mark the intended direction; use them to choose the next opening instead of picking the nearest dark passage at random.

Move from one stable surface to the next, using wall runs and goo jumps where the gap requires them. A common failure is catching the edge of a support instead of reaching its upper surface. The movement may register, but the extra climb wastes time and lets Dennis close the distance.

Line up the next support before jumping. Use the bounce surface for height instead of relying on a late mantle. Keep forward momentum when the path is collapsing or Dennis is directly behind you, and follow the visibly accessible route rather than trying shortcuts into unmarked rock passages.

The chase eventually reaches another blocked passage. The charge from Cavern A has already been used, so look around the nearby worksite and tents for a second dynamite pickup. Place it at the obstruction and detonate it to open the route back toward the camp. Continue through the newly accessible path and use the ladders and climbing supports to return to DJ and the crew lift.

The crew lift and the two-minute escape

When you return to the camp, find DJ and speak with him. The key is now available. Approach the lift's key-operated mechanism and use the Crew Lift Key at the designated slot. The system accepts it, and the lift can now operate.

Start the elevator with DJ. Dennis attacks during the ascent and knocks Jordan away from the lift, turning the escape into one final climb. The last chase gives you two minutes to catch the moving elevator.

The objective is to reach the rising platform, not to defeat Dennis in a conventional fight. Move immediately toward the accessible goo surfaces when the timer begins. The first section is a series of fast jumps between raised ledges and bounce platforms; look for the next launch surface before jumping from the current one.

Missing the launch point can send Jordan too low to reach the next ledge. Landing near the bottom edge of a wall instead of the intended platform also costs valuable time. If the route appears to stop at a vertical wall, check for a nearby elastic surface or climbable support. The answer is usually another upward movement, not a return to the lower floor.

The middle section continues across suspended supports and more goo platforms. Do not stop to watch Dennis. Focus on the next landing, the jump height, and the forward direction. Some jumps allow generous forward movement, while others require a controlled departure from the bounce surface. Repeatedly overshooting the same platform is a sign that the jump needs a shorter approach or a different takeoff angle.

There is no collectible or additional key to find during the timer. Any detour away from the marked climb only reduces the time left to catch the lift.

The final section pushes Jordan toward the elevator as Dennis closes in. Continue across the last bounce surfaces and platforms until the game confirms you have caught up. Once the elevator encounter begins, follow the interaction and movement sequence to deal with Dennis's final attack. This is not another open arena with a power panel or additional switches. The confrontation resolves as Jordan reaches the elevator.

The fourth pedestal

Before you start the final lift sequence, check the camp for the fourth and final pedestal. If you collected the stuffed animal after the opening chase and kept it through the chapter, place it now. The pedestal is near the crew lift area, and reaching it without the toy does not complete the placement.

If you missed the stuffed animal, level select lets you replay Chapter 4. The collectibles guide has the exact pickup spot, and the achievements guide explains how the four pedestals connect to the bonus sequence.

Mistakes that cost first runs

• Missing the stuffed animal after the opening chase. It is on the ground behind the first stretch of cavern. If you skip it, you cannot finish the fourth pedestal in this run.
• Trying to enter Cavern B without dynamite. The entrance is blocked. Go to the back of Cavern A first.
• Reusing the Cavern A charge on the return obstacle. The second blocked passage needs its own charge, found near the return worksite.
• Searching for the key on the ground floor of the spire. The Crew Lift Key is at the top of the climb, on the expedition member's remains.
• Stopping during the two-minute chase. The timer does not pause for Dennis's animations. Keep moving toward the lift.

FAQ

How long is Chapter 4? Most first runs take 60 to 90 minutes. The chapter is shorter than Chapter 3, but the camp loop and the final timed climb add replay time.

Can you kill Dennis? No. Dennis is an encounter, not a boss with a health bar. The special-spectrum lights repel him at the camp, and the final sequence resolves when Jordan reaches the elevator.

Where is the Allosaurus tooth? In Dennis's lair, among the collected objects. Pick it up before returning to DJ.

Where is the Crew Lift Key? At the top of the spire in Cavern B, on the remains of a former expedition member. You need dynamite from Cavern A to open the entrance.

What happens if the two-minute timer runs out? You restart from the checkpoint at the start of the ascent. The timer does not carry over between attempts, and there are no collectibles to grab during the climb.

Is Chapter 4 the last chapter? Yes. It is the final main-story level. Finishing it unlocks the Finally achievement and the ending sequence.

What to do next

Chapter 4 ends with the crew lift and the surface. If you want to understand what the final scene means, read the ending explained guide. For the full story in order, including Dalton's tapes and the Project Pilgrim records, see the story explained guide. The Dennis guide covers the Hybrid's role and the clues hidden in DJ's dialogue.

If you are replaying for collectibles, the collectibles guide lists every amber, tape, and note by chapter. The achievements guide explains the four pedestals and the bonus sequence.

Sources

• Terrible Lizards on Steam — release date, price, and platform details.
• PlayStation Blog developer interview — creature design and movement references.
• Terrible Lizards official site — setting and premise.
• Steam news hub for Terrible Lizards — patch 1.0.9 notes and developer Q&A.

Official source: Terrible Lizards on Steam — release date, price, platforms, and patch notes.