#but Ky and Testament have engraved it into their hearts

[nottoxicfr]

Don’t read this if you don’t want spoilers because Daisuke told me in a vision that this happens in the next DLC’s story addition!! The Holy Order Combination Formation is the most powerful attack!!

[gear-project]

So, did Kliff ever get into the trend started by Sol and Ky and inscribed his beliefs/ideology into his belt plate?

It seems that was something started by the younger soldiers as a way to boost morale.

Particularly the more religiously devout, like Ky (HOPE), Leo (PRIDE), and Malbeth (SACRIFICE).  Sol's engraving (FREE) was more in rebellion to Ky's.

Kliff already had something that motivated him to fight: the man Frederick who had saved his life as a child, and the boy Testament who reminded him he was still 'human' as an adult.

Still, if there was an ideology he believed in, or a faith he kept...

Perhaps it would have been "ENTRUST", to believe in the children of the future and give them the skills and tools they needed to bring back Peace and end this war.

Kliff had no doubts in his heart that he was going to Hell for his actions, but before that day would come, he would strive his utmost to establish a future Humanity could thrive in, though he had a great deal many regrets for his son Testament, his wish was that his son survive as well.

He gave his life so that Humans would be given more time to understand Gears and come to terms with them, ending the war for good.