When it comes to finding a great conflict to tell a compelling story, you don't get much more classic than sibling rivalry - which is why Thor and Loki almost had a brother in the MCU.

So it's no surprise that every movie in the Thor franchise which depicts Norse gods smashing monsters and each other with fists, hammers, and anything else within arm's reach uses sibling rivalry as a launching point in all three installments. The first two feature the conflict and subsequent reconciliation between brothers Thor and Loki as the most important features of their plots. Meanwhile, Thor: Ragnarok takes things a step further by introducing a third member of Odin's brood, Hela, who takes over Asgard and motivates her feuding younger brothers to work together to defeat her.

But as Marvel Cinematic Universe fans have since discovered, plans were underway behind the scenes to give Thor and Loki yet another, different sibling a brother who might be more familiar to comic book readers and lovers of Norse mythology. That's right, Balder the Brave was almost introduced to the MCU to further complicate Thor's family tree.

Former Marvel Studios head of visual development Charlie Wen sent MCU fans into a frenzy back in August 2018 with a single Instagram post. Wen posted concept art for Thor: The Dark World that revealed his take on adapting longtime Thor comics character Balder to the big screen. While the character's inclusion in the film was eventually scuttled, it's exciting to imagine how the MCU might've been different had Balder survived pre-production.

So what's the big deal about Balder? Well, for starters, he's got more right to the throne than either Thor or Loki at least if Marvel Comics and Norse mythology have anything to say about it. The films depict Frigga, played by Rene Russo, as Thor's mother. But outside of the films, it's Gaea, the Earth goddess, who is Thor's real mom, while Frigga is actually his step-mother.

Wen explained the character's importance during our exclusive interview:

However, the filmmakers behind the MCU know when to stay faithful to the comics, and when to streamline and simplify in order to keep the average moviegoer interested. It's one of the reasons the MCU works as well as it does and introducing Balder to the mix in The Dark World would've made a mess of an already pretty complicated story one featuring spacefaring Dark Elves, a reality-warping Infinity Stone, and Kat Dennings.

But while Wen and the rest of the production team tried to bring Balder into the fold, ultimately the biggest hurdle was just that there was no easy way to introduce the character into the MCU's increasingly complex continuity. At least, there weren't any that also gave him the importance the comics says he should have.

Wen left Marvel Studios to pursue his own creative endeavors in 2014, so he's not involved in the future of the MCU at least not directly. But as it turns out, much of the design work he did at the company still pops up in Marvel movies so many years later. So, despite the fact that we've yet to see Balder appear in the MCU to this point doesn't mean Wen's designs won't make it onto the big screen sometime in the future.