House of the Dragon is about to start truly living up to its name. In a new trailer for the second half of the season, the freshman series teases the upcoming cast change as civil war threatens to engulf Westeros in fire and blood.

Thus far, House of the Dragon centered upon a younger Rhaenyra Targaryen (Milly Alcock) and Alicent Hightower (Emily Carey) as the two young women struggled under the weight of their positions in the courts of King's Landing. Both girls had a lot of growing to do, which unfortunately drove a wedge between them. This all came to a head in House of the Dragon episode 5 of the season, "We Light the Way." Rhaenyra was wed to her cousin, Ser Laenor Velaryon (Theo Nate) following rumors that she had slept with her uncle, Daemon Targaryen (Matt Smith). Alicent discovered that Rhaenyra had lied to her - Rhaenyra did not sleep with Daemon, but with Ser Criston Cole (Fabien Frankel). In Westeros Medieval-inspired society, virginity is a virtue, and Alicent took this as an affront, finally turning the two best friends into enemies.

RELATED: House of the Dragon Episode 1 Uploaded to HBO Max YouTube Channel

In a new trailer, HBO has now highlighted the cast change among the younger cast. Though there's talk of bringing the young actors on for House of the Dragon season 2 in flashbacks, Rhaenyra will now primarily be portrayed by actor Emma D'Arcy, and Alicent will now be portrayed by Olivia Cooke. In the trailer, Cooke's Alicent points out that it's been at least 10 years since the events in "We Light the Way." Rhaenyra has had three children of her own ("What are children, but a weakness?" Larys Strong says in a voiceover), while Alicent has four, including the teenage Aegon, whose father, Viserys, passed over when naming Rhaenyra as heir.

As a teenage Aegon (Ty Tennant) is shown on screen, Alicent tells him he must prepare to be king as the rightful heir to the throne. Rhaenyra's children's legitimacy is called into question as Alicent speaks to an aged King Viserys, who looks to be in rough condition. Emma D'Arcy's Rhaenyra holds onto a young Joffrey Velaryon (her son, named after her husband's late paramour) as factions form to oppose her ascension. Elsewhere, Daemon has married Laena Velaryon (Nanna Blondell), who now rides the massive dragon, Vhagar. Laena has given birth to a daughter by Daemon, Baela, and is pregnant with another as she urges Daemon to return to Westeros. The Dance of the Dragons is about to begin.

The trailer is short but packed with teases for what's to come. Fans who have read Fire and Blood, the history of House Targaryen, are sure to notice more than a few Easter eggs. Furthermore, Cooke and D'Arcy's portrayals of their respective characters are on full display, both of them dripping with animosity towards the other.

It seems that there are still a few episodes for the Dance to begin in earnest. Fire and Blood points out that the first "battles" of the Dance were fought with words, but the battles on dragonback will have to wait for a later date. Season 2 will doubtless feature bloody spectacle after bloody spectacle as the realm tears itself apart, and with George R.R. Martin teasing a Red Wedding-level scene in House of the Dragon, the show will be an unflinching take on the horrors of war.

House of the Dragon airs Sundays at 9 PM EST on HBO.

MORE: The Idol: Everything We Know About The Upcoming HBO Series

Source: Game of Thrones/YouTube