I want to be in this. . . 

How about kind of like Chrono Trigger? The time period may advance, but effectiveness is based on weapon's various advantages. Zeal was the most advanced society until the end of the world, and it existed in 12,000 BC. That's because Zeal used magic, and 2000 used advanced technology. 

Throughout the setting, powerful things still existed based on reason. For example, Excalibur is a heavily powerful sword. If it's enchantment is strong enough, it can cut through a forcefield.