onslaught faced a crippling defeat at the battle of the nexus. 64% of his armies ships had been destroyed by the Goliaths. he was forced to watch as a massive energy bolt incinerated the entirety of his ship, killing him.

but it was not the end. the power the supreme one gave him ensured that. instead, his soul was sucked into the nexus itself, and sent hurtling through the void, searching for a suitable body.

it just so happens that an earth pony foal was being born at that moment.