A single ex Capcom and Epic Games Dev is responsible for the phycis in Clair Obscura, which provides some more anime style animation physics in games is used by Clair Obscura and other anime game titles.

Independent game dev Kazuya ‘Okazu’ Okada’s open-source physics plugin for Unreal Engine and it has help many teams to acheive some of the more anime and bouncy movement in character animations without keyframe animating them manually.

See his tweet on X about the tech used in unreal engine.

I do feel that this plugin is quite useful if you want to recreate some of the bouncy animation physics seen in anime games like idolmaster.

The tool looks like it can save time for game developers making more animations with automations, and with a smaller team. It is quite a feat what the team for Clair Obscura can do with some of these plugins.

Free and open sourced

There is a paid version of the plugin on the FAB Store for Unreal engine but you can grab the opensource version and tweak things around.

This is a huge win for small indie teams that might not have the budget to pay for a dedicated plugin developer and with shared knowledge other developers benefit from open sourced development. Though I think you can get a personal licese to support the developer.

Quite a few games have used it such as Stellar Blade, Fata Fury and Tekken. (See their Adoption Page)

What it does

Kawaii Physics is a simple pseudo-physics plugin for Unreal Engine.
It allows you to easily and cutely animate things that sway, such as hair, skirts, and breasts .

Features:

• Physics control based on animation and character movement
• Easy setup with a single KawaiiPhysics node in the AnimGraph
• Supports sphere, capsule, and plane collisions, which can be intuitively adjusted in the viewport
• Stability that prevents the skeleton from stretching or shrinking even if calculations fail
• Lightweight algorithm that does not depend on PhysX
• External forces such as wind and gravity can be applied for artistic purposes
• Parameters can be saved and shared using DataAsset and PhysicsAsset

How to install?

Get the latest from their Github Page or FAB. and the Getting Started Guide and the Deep Wiki on how to use in Unreal Engine.

Clair Obscura Expedition 33

Link:

Github Page:

https://github.com/pafuhana1213/KawaiiPhysics/blob/master/README_en.md

Tutorials:

https://dev.epicgames.com/community/learning/tutorials/d1Z9/unreal-engine-how-to-setup-kawaii-physics-in-unreal

Automaton Media Article: https://automaton-media.com/en/news/clair-obscur-expedition-33-uses-kawaii-physics-which-comes-as-a-pleasant-surprise-to-the-plugins-creator/

Games Radar Article: A single former Capcom dev is responsible for a ‘Kawaii Physics’ plugin used in many Unreal Engine games, and he was thrilled to learn that Clair Obscur: Expedition 33 also uses it

G2A: https://www.g2a.com/news/latest/how-clair-obscur-expedition-33-uses-kawaiiphysics-to-add-visual-charm/