Monster Hunter Stories 3: Twisted Reflection locks its rarest Monsties behind a gatekeeper system that rewards players who know where to look. Invasive Monsters block access to every Endangered Species den in the game. You'll need to hunt each one down, solve a battle puzzle to force it to retreat, then finish it off inside the unlocked den to claim your egg.
What Are Invasive Monsters?
These aren't standard field encounters. Invasive Monsters are souped-up variants of existing monsters hidden in hard-to-reach areas of each region. Here's what you need to know before tracking them down:
- They only spawn at night. Don't waste time searching during the day.
- Endemic life acts weird near their territory, functioning as a compass to guide you in.
- Eerie music kicks in as you get close to their location.
- All Invasive Monsters are at least Level 75. Show up prepared.
- You can't just beat them down on first contact. Each one demands a specific in-battle puzzle solution to trigger a retreat before the den opens.
All Invasive Monster Locations by Region
Azuria
Azuria has three Invasive Monsters spread across its zones.
- Invasive Species 1 (Invasive Yian Garuga): This one's mandatory. You'll run into it during Act 1, Chapter 6 in the Sunpetal Plains as part of the main story.
- Invasive Species 2 (Invasive Seregios): Start at the Mirror Lake Catavan Stand. Mount a Flying Monstie and ride the updrafts above Mirror Lake to reach the cliff marked by the blue arrow on the map. At night, the endemic life forms a glowing path pointing to the entrance.
- Invasive Species 3 (Invasive Plesioth): From the Mirror Lake Catavan Stand, use a Royal Ludroth or Plesioth to swim north through the channel into a cave. You can also approach from the east on land and drop down at the water entrance.
Canalta Timberland
Canalta Timberland contains three Invasive Monsters. One shows up during the main story.
- Story Invasive (Invasive Arzuros): You'll fight this one automatically during Act 2 as part of the main narrative.
- Invasive Species 1 (Invasive Shogun Ceanataur): From the Lookout Point: Howlingyowl Forest Catavan Stand, drop into the ravine directly south. Pass under the waterfall into the cave beyond.
- Invasive Species 2 (Invasive Nerscylla): From Camp: Blessing Hill, glide across the ravine toward the narrow opening on the far side. Look right for elevated terrain to make the crossing easier.
Tarkuan
Tarkuan has two Invasive Monsters in its rocky, vertical terrain. Bring a Climbing Monstie for both.
- Invasive Species 1 (Invasive Diablos): From Lookout Point: Rococo Rocks Catavan Stand, glide southeast to the ground floor. Find the ravine opening marked on the map, follow the path, then climb the wall at the end.
- Invasive Species 2 (Invasive Odogaron): From the Rococo Rocks Catavan Stand, glide south to a column with a tall updraft. Ride that updraft back northwest into an opening in the rockface. The Invasive Monster's territory starts deep down the path.
Serathis
Serathis has one Invasive Monster. From the Lookout Point, glide northeast to the tops of the rock formations and hop across them to find the path entrance marked by the curved arrow on the map. The lone Invasive Monster here is the Invasive Khezu.
Serathis den entrance route
Key Puzzle Solutions at a Glance
Here's a quick reference for what each Invasive Monster needs to retreat. Full solutions contain spoilers, so these stay high-level.
Why Endangered Species Are Worth the Effort
Every Invasive Monster you repel opens an Endangered Species den, giving you access to eggs for rare Monsties unavailable anywhere else in MHS3. These are some of the strongest companions in the game, and the puzzles guarding them reward players who pay attention to environmental storytelling instead of brute-forcing their way through.
Patience matters here. Collect every clue, read Rudy's dialogue carefully during battles, and watch for the retreat trigger. It typically fires after Rudy says, "So this is where the real fight begins!"
Make sure to check out more:
Frequently Asked Questions (FAQs)
When do Invasive Monsters appear in Monster Hunter Stories 3?
Invasive Monsters only appear at night. Visiting their territory during the day yields nothing. Watch for strange endemic life behavior and eerie background music as signs you're in the right area.
What level should I be before fighting Invasive Monsters in MHS3?
All Invasive Monsters are at least Level 75. Get your party and Monsties to a comparable level before attempting these encounters. Coming in underprepared will likely result in your party getting one-shot before you can trigger the retreat condition.
Can I fight the same Invasive Monster multiple times?
Once an Invasive Monster retreats, the Endangered Species den it was guarding becomes accessible. You can then attempt to slay the monster inside the den to claim the Endangered Species egg.
Do I need special Monsties to reach Invasive Monster locations?
Yes. Several locations require specific traversal abilities. Flying Monsties are needed for updraft crossings in Azuria, swimming Monsties like Royal Ludroth or Plesioth open water routes, and Climbing Monsties make navigating Tarkuan's vertical terrain significantly easier.
