The Unspoken

Classically, Black Bolt is the ruler of the Inhumans but, before he was on the throne, it was the powerful being known as The Unspoken who ruled them.

The Unspoken first appeared on panel as recently as 2009 in Mighty Avengers #27 – his story being that, while he ruled the Inhumans fairly and justly, he also stole the Slave Engine – their greatest weapon – and hid it for fear of it corrupting them.

This led Black Bolt – the young, would-be king – to lead a revolt against him, which resulted in him and a small group of other Inhumans overthrowing him and Black Bolt ascending to the throne.

With Black Bolt on the throne in the MCU, it would be awesome to see The Unspoken – who is the living embodiment of the process known as Terrigenesis (the process through which the Inhumans gain their powers) – taking on his own race, looking for revenge, as he is capable of spawning almost any power he wishes, would be one hell of a threat for them to face and an awesome villain to see in live action.

In the comics, he returned to Atillan looking to marry Medusa, which brought him into conflict with the Inhumans – and he has also proven to be a powerful enough threat to take on entire teams of Avengers on his own.