The mutant-hunting Sentinel robots remain one of the X-Men's most formidable opponents to this day. Invented by Bolivar Trask, the Sentinels are designed to identify and overpower any mutants hiding in plain sight.

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Over the years, there have been many new models of this machine. Each new version becomes better at performing the initial function of eliminating mutants. One of the most capable of all these models is the Master Mold. One of the largest and most powerful Sentinels, the Master Mold is quite mysterious in its nature and origin. Here are 10 secrets about the Master Mold that fans should know.

10 10. Tri-Sentinel Master Mold

When Mendel Stromm got his hands on the Tri-Sentinel, he was very excited to use the machine to get revenge on his hated enemy, Spider-Man. Stromm was then approached by a mysterious man who gifted him with an even greater robot.

This mysterious benefactor gave Mendel Stromm a unique version of the Master Mold Sentinel. This Master Mold didn't just produce normal Sentinels as most Master Molds due. This one specialized in creating Tri-Sentinels. Spider-Man destroyed this Master Mold not too long after, but in its day it was one of the most powerful Master Molds ever seen.

9 9. Days Of Future Past

In the alternate future timeline called Days of Future Past, the world has become overrun with Sentinel robots. Killing mutants in every corner of the world, theses machines have evolved into one of the most dangerous models of all time, called Nimrod.

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There are only a few Master Molds left in this new timeline. One of them has the sole purpose of creating new Nimrods. These machines are then sent out into the hopeless world where they hunt down all that remains of mutant-kind.

8 8. Ecuador And The Wild Sentinels

Wild Sentinels destroying Genosha

There is another Master Mold living in secret within the jungles of Ecuador. Like a few of the aforementioned Master Molds on this list, the model located in Ecuador also had a unique function.

This particular Master Mold creates Wild Sentinels. The Wild Sentinels are unique in that they can absorb various materials into their structure in order to create different shapes. These various shapes are specifically designed to increase their battle effectiveness, making them much more adaptable and unpredictable.

7 7. The Retribution Virus

Master-Mold

During the Cyclops: Retribution graphic novel, one of the Master Molds created a mutant disease known as the Retribution Virus. Designed to wipe out humanity, this virus nearly achieved its intended goal.

Unfortunately for the rest of the world, the virus mutated to the point where it was also a threat to humanity as well. The X-Men were narrowly able to defeat the Master Mold and prevent its evil plan.

6 6. Merged With Stephen Lang

Master Mold and Sentinels in X-Men comics

A scientist specializing in both genetic mutation and robotics, Stephen Lang has long been one of the X-Men's most influential enemies. After Bolivar Trask passed away, Lang took over the Sentinel program and tried to uphold its 0riginal purpose of destroying mutant-kind.

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It appeared that Steven Lang had died after the events of Project Armageddon. This was not the case. In reality, Lang had crashed his gunship near a Master Mold. Crawling from the wreckage, he made it into his machine and merged with it. This very same Master Mold that merged with Lang was also responsible for creating the Retribution Virus.

5 5. There Are Many

Ultimate Sentinels

When the X-Men first battled the Master Mold it appeared that there was only one. This one Master Mold had been responsible for mass-producing an incredible number of Sentinel robots.

What the X-Men didn't know was there were many Master Molds hidden in various locations across the world. Whether these machines were created by Trask, Lang, or both remains to be seen. Regardless, one of the most terrifying secrets about the Master Molds is that there are many out there, quietly producing additional Sentinel armies.

4 4. Sentient

MK I Sentinel

Trask developed the first Master Mold using a supercomputer. Giving it such heightened intelligence may have seemed like a good idea at the time, but the decision has since had disastrous consequences.

The Master Molds, starting with the original model, have become self-conscious. As sentient beings, the Master Molds were able to disobey their masters and programming. After doing so, the robots used their vast powers to further various nefarious schemes.

3 3. Bastion Is Half Master Mold

Bastion X-Men Joe Madueria

A supervillain and long-time enemy of the X-Men, Bastion's origins were quite mysterious when he made his first appearance. He quickly rose to power within the U.S. Government and became the head of an anti-mutant strikeforce.

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It was later revealed that Bastion's origins were perhaps the strangest of any supervillain ever. Bastion was actually created when a Nimrod was merged with a Master Mold. Although he appears to be human, he is actually the result of two different Sentinel models being combined.

2 2. Partially Invented By Tanya Trask

It was always believed that Bolivar Trask invented the first Master Mold all by himself. Later on in X-Men comics, it was revealed that Madame Sanctity, also known as Tanya Trask (daughter of Bolivar Trask), originally programmed the first Master Mold.

A time-traveling member of the Askani Sisterhood, Madame Sanctity had the sole purpose of finding and killing The Twelve. The Twelve are a group of mutants that are said to bring about the rise of Apocalypse. While the Master Mold does not succeed in killing all of these mutants, it did bring about much chaos in the mutant community thanks to Tanya's programming.

1 1. Wants To Take Over Humanity

Master Mold

Trask created the Sentinels with the one goal of protecting mankind from the mutant menace. Due to the Master Mold's growing sentience, it began to look for any solution possible to help achieve this incredibly difficult goal.

In the end, the Master Molds came to the conclusion that there was only one way to save humanity: enslave it. After taking control of humanity, the Sentinels would be able to very easily protect it from mutant-kind.

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