2When Invasion of Arcavios enters the battlefield, it triggers, returning Walk the Aeons from your graveyard to your hand, or searching your library for Walk the Aeons and putting it into your hand, if needed.
3Cast Walk the Aeons by paying .
4Brinelin triggers, returning Invasion of Arcavios to your hand from the battlefield.
5Resolve Walk the Aeons, causing you to take an extra turn after this one.