Thesius XII: Developing a Classic Amiga Shoot 'Em Up
Back in the golden age of the Amiga, I developed Thesius XII, a fast-paced shoot 'em up inspired by the arcade classics of the time. The game was my attempt at pushing the limits of the Amiga hardware while delivering an engaging and action-packed experience. Sadly, the game was never fully completed, but in 2000/2001, I released an 'as is' version featuring three levels. Despite missing final polish, it remains a nostalgic favorite for many retro gaming enthusiasts.
Inspiration and Design
The concept for Thesius XII was heavily influenced by IREM’s R-Type and Tecmo’s SilkWorm, two of my personal favorites. I wanted to create a game that blended intense shooting mechanics with strategic enemy patterns, requiring both reflexes and tactical movement. The art style and design leaned into the aesthetic of futuristic space battles, filled with vibrant explosions, detailed sprite work, and smooth scrolling backgrounds.
Technical Development and Features
The game was designed for a stock Amiga 500 running a 7MHz 68000 CPU, 512K memory, and the original chipset. Developing on this hardware came with its own set of challenges. Memory constraints, CPU limitations, and optimizing the rendering pipeline were crucial to maintaining smooth gameplay. One of the biggest hurdles was handling a large number of on-screen enemies without bogging down performance. To solve this, I implemented efficient sprite management and custom routines for object culling and collision detection.
Some of the standout features of Thesius XII included:
Development Challenges
One of the trickiest aspects of development was optimizing graphical effects for smooth performance. The intro, while simple by today’s standards, was particularly challenging to run efficiently on a stock Amiga 500. The Terminal Screen in Level 1 was another technical feat, combining both low and high resolution modes within the same screen, with palette splits on every scanline and dynamic text rendering.
Another personal highlight was the homing missile system, which I spent a great deal of time perfecting. Even now, looking back, I think it worked out quite well.
Release and Reception
Prior to September 16, 2003, a multi-level version had never been released, as the game remained incomplete. However, we felt it was a shame not to share what we had, even though it lacked the final two levels and additional polish. Thesius XII v95 was first reviewed in Amiga Format (August 1995) in their PD section, and it was featured again in a follow-up issue, highlighting promising Amiga developers.
Legacy and Follow-Up
Years after Thesius XII, I revisited the concept with Thesius XIII, a tech demo for PlayBASIC. While it wasn't a full game, it showcased advanced techniques for handling sprites, movement, and rendering in a modern game development environment.
Even though the full vision of Thesius XII was never realized, the game remains one of my favorite projects from the Amiga days. It was a challenging but rewarding experience that shaped my approach to game development. For those interested, an emulated version of Thesius XII is available online, best played using the latest version of WinUAE.
Would you like to see a modern reimagining of Thesius XII? Let me know your thoughts!
