Guardians of the Galaxy: Which Infinity Stone Was That?

Warning: Minor spoilers ahead for Guardians of the Galaxy, in theaters now.

While Marvel Studios have been hesitant in the past to identify just which of the Infinity Gems was the MacGuffin in any given movie, Guardians of the Galaxy director James Gunn has no such issues, it seems.

The "orb" at the center of the film, which houses one of the Infinity Gems (called Infinity Stones in the movies, we learned), insulates the world around it from a purple stone, suggesting to comic book fans that it might be the Space Gem. It doesn't act in quite the way the Space Gem would in the comics, though, and both Gunn and Marvel Studios head Kevin Feige have been open about the fact that the stones might not sync up 1:1 with their comic book counterparts.

A fan took to Twitter to ask Gunn about the one used in the film...

“@sensmile11: @JamesGunn Are you allowed revealing which infinity stone was used? Loved the movie, you nailed it” Power stone.

— James Gunn (@JamesGunn) August 3, 2014

Both Nebula and Drax have possessed that stone in the past (along with many others, including Thanos). In the comics, it's red. Here's how the Marvel Wiki describes its powers:

The red Power Gem gives the owner access to all power and energy that ever has or will exist, and can back the other gems and boost their effects. Its most basic powers grant its user unlimited stamina and can increase the user's strength to unlimited levels depending on how much the gem is drawn upon. It allows the user to duplicate practically any physical superhuman ability and become invincible. It can also be used as an unlimited power supply for any machine.

At one point, Feige said that the Tesseract was the Space Stone and the Aether from Thor: The Dark World was the Reality Stone. Timeline-wise, we can't confirm whether that was before or after the last time he was unwilling to answer the question.