Jurassic World Evolution is an excellent strategy game. It requires players to keep a theme park full of hostile dinosaurs running smoothly, so they can earn money from visiting guests while preventing (or at least minimizing) deaths when breakouts happen.

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Throughout the game, players must meet certain requirements to unlock the many different dinosaur species available. Some dinosaurs are tricky due to difficult missions, the hybrids require tons of research, and some of the most dangerous dinosaurs in the game are locked behind stiff challenges. All of this is intended to ensure that only the best park managers have access to these nightmarish (yet crowd-pleasing) monsters.

10 Styracosaurus

The Styracosaurus is available in the deluxe edition of the game and resembles the more famous Triceratops, albeit with more spikes. This dinosaur can be researched only after the player completes all of the entertainment division missions on Isla Muerta.

Fans of the game will recognize the challenge almost instantly, as Isla Muerta is one of the more difficult islands early in the game. One mission in particular requires players keep a Velociraptor, Dilophosaurus, and Ankylosaurus in their separate enclosures without them breaking out... while the power stations are being sabotaged and the gates malfunction. It’s considered one of the tougher missions in the game.

9 Kentrosaurus

The Kentrosaurus is a herbivore that can be researched after players unlock it by completing all of the entertainment missions on Isla Pena. Isla Pena is infamous for being the hardest island in the original version of the game, which means its missions are that much more challenging.

On Isla Pena it’s always night, the park is small, and there are a lot of storms. Once a dinosaur breaks out, it becomes very difficult to tranquilize and bring back to the pen. The dinosaurs also seem much more abrasive than usual, perhaps because of the perpetual night. Players will have a tough time unlocking this dinosaur on this dark isle.

8 Gigantosaurus

As tough as unlocking the Kentrosaurus was, the Gigantosaurus is much tougher because it requires completing the Security missions on Isla Pena. Given the logistical nightmares of Isla Pena, this can be really difficult.

One mission has you loan out some particularly aggressive dinosaurs. When you get them back, they are sick, uncomfortable, and angry. It’s your job to get them back to full health and comforted, while contending with their attempts to break out (and the power outages that could very well open the door wide for these cranky beasts). That's just one mission. If you pull them all off, this cool carnivore is your reward, but it's a heck of an ask.

7 Troodon

With the Secrets of Doctor Wu expansion pack, players were introduced to a secret part of Las Cinco Muertes, where Doctor Wu has been cooking up some interesting and dangerous new dinosaurs. This expansion introduced some of the toughest missions in the game, so obtaining dinosaurs like the poisonous Troodon is a true challenge.

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The Troodon is unlocked by completing Security division missions in the Muerta East facility, the aforementioned secret area Doctor Wu was working in. These Security missions were tough and required players to have a reputation score of 40% with the Security Advisor to unlock this poisonous creature.

6 Olorotitan

While the Troodon was unlocked during the Security missions, the Olorotitan is obtained after completing the science missions and achieving a 40% reputation rating with the science advisor. This may seem easier when considering the Security missions, but the difficulty comes from actually gathering the raw material to build this dinosaur.

The Olorotitan only has one dig site from which to obtain fossils for genome extraction, meaning you’re limited to one expedition at a time instead of the three teams you could send out for the Troodon. This meant more farming, which meant it took longer to obtain.

5 Indominus Rex

Now, we cross into the dangerous area of hybrid dinosaurs, which Doctor Wu is infamous for. Every hybrid in the game requires a number of steep requirements to unlock, but can be some of the best (or at least the most memorable) dinosaurs in the game.

Indominus Rex is unlocked in the base game after accessing Isla Sorna, obtaining 100% on both T-Rex and Velociraptor Genome research, building a total of four research centers, and having $2,000,000 in cash to cover all expenses. If you meet all these requirements you have the iconic dinosaur from the movie to run around your park.

4 Indoraptor

The infamous dinosaur from the second movie, the Indoraptor is obtained in the Fallen Kingdom update. It’s considered the toughest dinosaur to obtain in the base game.

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For starters, you need a research center on each of the game’s five islands, a security rating of 90% on Isla Sorna, and $2,710,000 on hand. Then, you must get the Velociraptor genome up to 100% and the Indominus Rex genome up to 100%. That’s right, you need to unlock the Indominus Rex before you can even begin to create this nightmare fuel.

3 Spinoraptor

The Spinoraptor is a tough dinosaur to obtain, and the first of three hybrids reserved for Doctor Wu’s special missions. It requires beating all of the missions on Muerta East, unlocking both the Troodon and Olorotitan, constructing five research centers, beating the third mission at the Tacano Research Facility, having $1,400,000 cash, and getting Spinosaurus and Velociraptor genome up to 100%.

Granted, you’ll accomplish some of this by pursuing the previous dinosaurs on the list, but it’s still a significant investment of time, money and skills. Not to mention the headache that comes with beating Muerta East.

2 Stegaceratops

The Stegaceratops is arguably more difficult to unlock than the Spinoraptor, solely because you gain access to its mission after you unlock the Spinoraptor. It has roughly the same requirements (adding the need to level the Stegosaurus and Triceratops genome up to 100%).

It’s an iconic dinosaur that fans will recognize from previous games. It was rumored to have been intended for an appearance in the first Jurassic World movie, but was scrapped so it wouldn’t take any of Indominus Rex’s thunder.

1 Ankylodocus

Perhaps the most difficult dinosaur to unlock in the game is the Ankylodocus. This dinosaur requires the completion of Muerta East, is the second to last mission in the Tacano research facility, requires unlocking of all other dinosaurs on this list, and 100% genome research for both the Diplodocus and Ankylosaurus.

This hard-shelled herbivore has the benefit of being immune to attacks from all other dinosaurs except the Indominus Rex, making it the toughest herbivore in the game. It’s strange the game’s final unlockable dinosaur is a herbivore, but the last mission unlocks Indominus Rex’s camouflage abilities, so there is that.

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