Principles of programming (C#, C++, JavaScript, PHP, HTML...)
Adiovisual arts(Composition, Adobe...)
Principles of UI and UX.
Animation (Blender, Unity)
Augmented and Virtual Reality.
Neuroscience.
Robotics.
Music creation.
On one hand: principles of games' theories, art and narrative. User experience, production and management.
On the other hand: Unity, Unreal using Blueprints and Phaser.