LEGO Batman Legacy of the Dark Knight Poison Ivy: Full Mission Walkthrough - Characters

LEGO Batman Legacy of the Dark Knight Poison Ivy: Full Mission Walkthrough

Complete walkthrough for the Poison Ivy mission in LEGO Batman: Legacy of the Dark Knight. Find all Venus Fly Traps, Waynetech Caches, and defeat the Snapdragon.

2026-05-21
LEGO Batman: Legacy of the Dark Knight Wiki Team
Quick Guide
  • LEGO Batman Legacy of the Dark Knight poison ivy is mission 16, taking place in the Botanical Gardens.
  • Primary Objective: Investigate the spread of mutant plants and locate Dr. Pamela Isley's hidden laboratory.
  • Boss Strategy: Defeat the giant Snapdragon by tethering its heads with Robin's cable launcher during its roar.
  • Key Reward: Completing this mission unlocks the Sonar Suit for Batman and the Batman & Robin outfit for Robin.
  • Collectibles: There are 5 Venus Fly Traps and 5 Waynetech Caches hidden throughout the mission.

Investigating the Botanical Gardens

The mission begins after the encounter with Kite Man. Batman and Robin, currently mentoring Jim Gordon’s daughter Barbara, must head to Robinson Park to investigate a monstrous plant outbreak. The Botanical Gardens serve as the epicenter of this botanical nightmare, where Dr. Pamela Isley (Poison Ivy) has been experimenting with a powerful growth serum.

Video Highlights:

  • Detailed walkthrough of the initial garden puzzles and character interactions.
  • Locations for early-mission Venus Fly Traps and hidden paths.
  • Demonstrations of Robin's cable launcher mechanics for traversal.

Upon entering the gardens, players encounter the first environmental puzzle. You must locate a plant pot on the right side of the entrance and move it to the dirt patch on the left. Once planted, the mutation serum causes the plant to grow rapidly, creating leaf platforms that allow Batman and Robin to reach the upper ledge. This area introduces the core mechanic of the mission: using growth accelerators to manipulate the environment.

Mission ComponentDetails
Mission Number16
LocationRobinson Park Botanical Gardens
Main EnemiesPlant Henchmen, Exploding Cacti, Rapid-fire Sprouters
Primary CharactersBatman, Robin (Dick Grayson)
Character Synergy

Always keep an eye out for dual-tether points. Robin is essential for pulling vines and creating tightropes, while Batman’s Batclaw is required for heavy environmental interactions.

Finding Dr. Isley's Lab

As you progress deeper into the gardens, the environment becomes increasingly hostile. After crossing the lilypads near the waterfalls, you will reach a corridor blocked by massive vines. Use the cable launcher to connect the tethers, clearing the path to the laboratory wing.

The laboratory section introduces Explosive Pods. These pods dispense small, cactus-like plants that charge toward the player and detonate on contact. It is vital to prioritize these pods, but note that the game prevents you from destroying the main pod if any mobile plant enemies are still active in the immediate vicinity.

1

Clear the Spawners

Defeat all active plant henchmen and exploding cacti in the room to make the central pod vulnerable.

2

Freeze and Shatter

Use Batman's freeze spray on the main pod to solidify its structure, then follow up with a melee strike to shatter it.

3

Navigate the Vents

Switch to Robin and use the slider mechanism to pump green growth liquid through the pipes, activating the next set of plant platforms.

Enemy TypeAttack PatternCounter Strategy
Exploding CactusCharges and detonatesRanged Batarang / Birdarang
Rapid-fire SprouterShoots seeds from a distanceShield or dodge roll
Whipping TentacleSlams ground in a straight lineJump over the shockwave
Toxic Gas Alert

Some corridors in the lab are filled with toxic green gas. Do not attempt to walk through these; instead, look for overhead grapple points or hidden switches to vent the room.

Collectible Locations & Red Brick Puzzle

For players aiming for 100% completion, the Botanical Gardens mission is packed with secrets. The most sought-after item is the Flower Power Red Brick, which adds a unique visual modifier to the game.

The Red Brick Puzzle: Inside the central greenhouse, you will find a glass case containing the Red Brick. To open it, you must interact with the plant stand to the right. You need to select two specific plants to combine:

  1. Select the Red Plant.
  2. Select the Bushy Green Plant. Planting these in the designated pots will cause a combined plant to bloom and then wilt, triggering the hatch to open.

Venus Fly Traps (5 Total)

  • Piece 1: Above the waterfalls in the first room.
  • Piece 2: Under the ledge after the first pod encounter.
  • Piece 3: Right-hand corner below the leaf tightropes.
  • Piece 4: On the ledge near the greenhouse entrance.
  • Piece 5: Hidden behind vines near the combine harvester.

Waynetech Caches (5 Total)

  • Cache 1: In the cave behind the waterfalls.
  • Cache 2: On the upper platform created by the orange flowers.
  • Cache 3: Tucked in an alcove after the first gas room.
  • Cache 4: Below the first whipping tentacle corridor.
  • Cache 5: In the secret room above the snapping mouth plants.
Collectible TypeReward
5 Venus Fly TrapsMission Trophy Piece
5 Waynetech CachesBonus Studs & Concept Art
Red BrickFlower Power Modifier
The Combine Harvester

Near the end of the lab, you can build a LEGO Combine Harvester. Use this vehicle to plow through the thick vertical vines. Don't forget to veer left before the final door to find the last Venus Fly Trap!

Poison Ivy Boss Fight Guide

The confrontation with Poison Ivy occurs in two distinct phases. Initially, she attacks from the ground using vine slams and explosive plants. Once her first health bar is depleted, she summons a massive, two-headed Snapdragon creature.

Phase 1: Dr. Pamela Isley Ivy will raise long vines that slam down in indicated paths. After the slam, the vine will spin 360 degrees, requiring a timed jump. When she rests on a central cactus to summon explosive plants, use the Batclaw to pull her down and stun her for a melee combo.

Phase 2: The Giant Snapdragon This phase is significantly more dangerous, as the creature utilizes acid vomit and shockwave stomps.

1

Avoid the Acid Beam

The Snapdragon fires a continuous beam of green liquid. Run in a wide circle to stay ahead of the beam's tracking.

2

Tail Snag

Wait for the creature to slam its tail into the ground. Jump the resulting shockwave, then use the Batclaw on the tail's pull-point to stun it.

3

Tether the Heads

When both heads let out a roar simultaneously, switch to Robin. Use the cable launcher to tether the two mouths together, leaving the boss vulnerable to a finishing move.

AttackDescriptionHow to Avoid
Acid RainArcing green projectilesStay out of the red circles
Tail WhipClose-range 360 attackKeep your distance
Strafe RunProjectile vomit from the airJump between the floating leaves
Falling Leaves

During the Snapdragon's strafe run, the ground becomes toxic. You must jump onto the leaves that appear in the air, but be quick—they fall shortly after you land on them.

Post-Mission Rewards & Next Steps

After defeating Poison Ivy and her Snapdragon, a cutscene plays featuring Batman and Robin discussing the city's power needs. Batman suggests that Bruce Wayne might be able to help fund a new, cleaner power plant for Gotham, while Robin expresses skepticism about Wayne's greed—a classic piece of LEGO humor.

Completion Checklist:

Mission 16 Completion Goals:

  • Defeat the Giant Snapdragon boss
  • Unlock the Sonar Suit for Batman
  • Obtain the Flower Power Red Brick
  • Collect all 5 Venus Fly Trap pieces
  • Reach the 'True Hero' stud requirement

The Sonar Suit is a vital unlock, as it allows Batman to shatter glass objects and navigate dark areas in future missions. Following the arrest of Poison Ivy, you must head to the GCPD rooftop to interact with the Bat-Signal, which officially concludes Chapter 3 and prepares the duo for "Operation Deep Freeze" involving Mr. Freeze and Bane.

New Suit Utility

The Sonar Suit's sonic pulse can also stun certain robotic enemies. Try using it in the open world to find hidden LEGO bricks behind glass storefronts.

FAQ

Q: How do I unlock the Poison Ivy mission in LEGO Batman: Legacy of the Dark Knight?

The Poison Ivy mission (Mission 16) unlocks automatically after you complete the Kite Man boss fight and the subsequent mentoring cutscene with Jim and Barbara Gordon.

Q: What is the correct combination for the Red Brick puzzle?

To unlock the Flower Power Red Brick in the greenhouse, you must combine the Red Plant and the Bushy Green Plant in the designated pots.

Q: How do I stun the giant Snapdragon boss in phase 2?

You can stun the Snapdragon by using the Batclaw on its tail after a slam, or by using Robin's cable launcher to tether its two heads together when it roars.

Q: Can I play as Poison Ivy after the mission?

Poison Ivy becomes available for purchase in the character grid once the mission is completed. You can then use her in Free Play mode to access plant-based puzzles.