The Emissary (Aggressor) of Old (古からの使者（アグレッサー）, Inishie Kara no Shisha (Aguressā)) is the eleventh episode of Hyperdimension Neptunia: The Animation. It first aired in Japan on September 20, 2013.
Held in a Planeptune prison, Rei Ryghts sadly ponders about how she came from being a social activist to where she is now. Subsequently, a dark force takes ahold of her.
At Lastation, Neptune tries to hand over tickets to the celebration to the other CPUs, but they don't share the same enthusiasm as her. Blanc rejects it and leaves. The others explain how Neptune is being insensitive about the fact that the other nations' Share energy plummeted into an all-time low. Vert politely declines Neptune's invitation and leaves, and Noire explains how she's currently busy. Before going back home, Neptune hands over the tickets to Noire and tells her that she's welcome to come anytime.
Outside Planeptune, while filming for her show, Abnes suspects the gathering of a lot of girls in Planeptune's Basilicom. Upon arriving, Abnes sees the event, but she thinks of it as a trick. She stumbles upon Neptune and Nepgear, both not remembering her. Immediately, Neptune is contacted by Blanc, wondering if she can make it to the celebration after all. Turns out that Blanc is calling her out in a forest.
In her CPU form, Neptune flies to the rendezvous, irritated about being called out while busy. Out from above, Blanc attacks her, but she deflects the attack on time. In the heat of the battle, Blanc demands Neptune's Shares. Neptune reminds her of their treaty of friendship, but Blanc accuses Neptune of stealing Lowee and the other nations' Shares. Before escalating any further, Rom & Ram arrives and protect Neptune, believing on their friendship, but Blanc warns Neptune about the possibility of war if she continues to ignore the situation, leaving Neptune to wonder what's going on.
Back in Planeptune, the festival continues on. Meanwhile in Lastation, Noire visits Anonydeath on his prison, who had contacted her for a talk. Anonydeath accounts Rei Ryghts as his client and the mastermind of the Eden case.
In Planeptune's prison, Rei breaks out of her cell. Suddely, the sky turns dark around Planeptune, and a landmass rises out of its grounds. Rei transform into a CPU form, claiming the nation as Tari. Having just arrived, Neptune wonders who she is. The insane CPU, affirming to have ruled longer than Neptune have, demands Planeptune's land and its inhabitants, which she claims to have owned in the first place. Not willing to give in to her demands, Rei threatens to fire a laser on Neptune, but Planeptune's CPU holds her ground. Changing her target, Rei aims the weapon at Planeptune's Basilicom and fires, splitting it in half.
After the laser's blast, communications were cut, isolating Planeptune from any outside help. Satisfied with herself, Rei asks Neptune again if she changed her mind, but Neptune states her resolve to protect Planeptune.
- Planeptune held the most Shares, while the other nations suffer from low amounts.
- Neptune held a festival to celebrate Planeptune's high Share count.
- Blanc warned Neptune of a possibility of war if she continues to ignore the situation of the Share distribution.
- Rei Ryghts is revealed to be the mastermind behind the Eden case.
- Rei revealed herself as Tari's CPU, an ancient nation, and she plans to take Planeptune all for herself.
Currently in her human form, Neptune is frustrated that she can't pre-order the console that is coming today after communications were cut, disregarding the current situation.
Neptune invites the other CPUs to the celebration in Lastation's Basilicom, which will be held at Planeptune's Basilicom. Tari, the landmass that Rei Ryghts rules over, rises from Planeptune.
Characters are shown in order of appearance.