Exarchon

Exarchon is a Transformer from the 2019 IDW portion of the Generation 1 continuity family.

You can't see me!

_{This character has no official visual representation in any Transformers product or media... yet, at least.}

Exarchon was the leader of the Threefold Spark presumably during the eponymous War of the Threefold Spark. Apparently, he should not have been trusted.

Fiction

2019 IDW continuity

Exarchon lost the War of the Threefold Spark, and like several others was exiled. However, some like Cyclonus remained unconvinced that he was truly gone. The Cracks Beneath Your Feet Part One

When Senator Orion Pax wondered whether he could still trust Megatron, Codexa claimed Cybertron once trusted Exarchon, to which Orion responded that Megatron was nothing like Exarchon. Orion Pax: Free Fall