Why Thanos Needed More Than the Reality Stone in 'Avengers: Infinity War'

Some fans believe Thanos could have achieved his goal of wiping out half of the universe with only the Reality Stone but the directors of Avengers: Infinity War have explained why this is not the case.

Spoilers for Avengers: Infinity War follow. Major spoilers!

When Thanos had attained the Reality Stone from The Collector on Knowhere, he was quick to display its power. It can change just about anything into anything he can imagine. Not only did he make Knowhere look like he had not completely destroyed it but he also turned Drax into a bunch of small shapes on the ground and turned Quill's bullets into bubbles. The entire sequence was narrated on the Avengers: Infinity War commentary track attached to the film's digital download.

"The bubbles obviously a function of the Reality Stone," co-director Joe Russo said. "Thanos has the ability to manipulate."

So, if Thanos can turn bullets to bubbles and erase people like The Collector with a thought, why can't he just erase half of the living beings in the universe already?

"We were asked by a 12-year-old in DC at a Q&A why Thanos needed all six Stones and why he didn't just use the Reality Stone to alter reality," Joe Russo said. "The idea being that only something so dramatic of disposing life in half the universe could be accomplished with the power of all six Stones."

As revealed when Drax and Mantis stood up after being reduced to shapes on the ground, the Reality Stone's effects don't appear to be permanent.

"We sort of used it as an impermanent solution to things," screenwriter Stephen McFeely said.

"It's illusory," Joe Russo added. "It creates illusions."

As it turns out, the moments which saw the characters being erased by Thanos snapping his fingers after rounding up all six Infinity Stones was the last thing the cast members found out about.

"The blip out sequence, we had gathered the whole entire talent, they are circled around our directors, and basically revealed to them that morning of that scene was happening, that some of them were gonna be disappearing," producer Trinh Tran said.

"The audience is so good at predicting stories that even just the smallest clue can tell them where the film is gonna go. So, we worked really hard to make sure none of the secrets of the film leaked," Joe Russo said. "It's about as massive a production as you can mount. About 6,000 crew members working on the film from around the world."

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