'The Legend of Zelda: Tears of the Kingdom' developers have explained how the game was a much bigger task than fans realised.
The Legend of Zelda: Tears of the Kingdom
The Nintendo game is still seen as a bit of a half sequel to 2017's 'Breath of the Wild', by using the same Hyrule but still building on the previous title.
However, lead physics engineer Takahiro Takayama said at the Game Developers Conference: "When I first saw the prototype, I thought this was going to be a great game.
"But I also knew: this was going to be very, very difficult... I said to myself: are we really doing this? Development is going to be chaos.
"The more I thought, the more I worried. I realised that sometimes, it's important to have the courage to push forward."
Technically, these challenges included having to create a "physics-driven world" and thus "create a system where unique interactions occur, without dedicated implementation".
He explained that, for the development team, "physics-driven" meant: "Objects have mass and moments of inertia - and they can be controlled using things like velocity and acceleration."
In the early stages of development, the team had relied heavily on a non-physics driven object, which is called a "kinematic rigid body".
However, these objects had "infite mass", which "meant chaos" for the developers.
He explained: "The clash between non-physics-driven objects and ultrahand, with a high degree of freedom, caused daily problems all over the land of Hyrule.
"It went something like this. I would hear something like: 'It broke!' or 'It went flying!' And I would respond with: 'I know - we'll deal with it later! Just focus on getting the gameplay together and trying it out.'"