House of the Dragon episode 6 introduces a new dragon to the mix – Laena Velaryon rides an absolutely massive creature that we haven't seen in the show before. This dragon is none other than Vhagar, the oldest and biggest of the dragons currently alive in Westeros. This fire-breather has a particularly epic history, as detailed in the works of George R.R. Martin. Now, before we go any further, the following is totally spoiler free, so you can read up on Vhagar whether you're up to date or not.