Þjálfi and Röskva

: Rǫskva [ˈrɔskwɑ]), also known as Thjalfi and Roskva,[1] are two siblings, a boy and a girl, respectively, who are servants of the god Thor.

In the Poetic Edda, Thor recounts an incident where Þjálfi is chased away by she-wolves but gives no additional information about him.

From the farm, Thor, Loki, Þjálfi, and Röskva head out to a vast forest in the realm of Jötunheimr.

The next night, Thor finds that he is unable to kill Skrymir, and the group sleeps in fear beneath an oak.

After the group spends the night at the keep, Útgarða-Loki reveals that he was in fact Skrymir and that Thor actually nearly killed him.

[5] While Röskva is absent, Þjálfi receives a single mention in the Poetic Edda poem Hárbarðsljóð.

The peasant's son Þjálfi takes one of the goat ham-bones and uses a knife to split it open, breaking the bone to get to the marrow.

Noting this new lameness, Thor exclaims that someone has mistreated the bones of his goats; that someone broke the ham-bone during the meal the night before.

Third notes that there is no need to draw out the tale, for: At realizing how terrified he has made the peasants, Thor calms down and from them accepts a settlement of their children Þjálfi and Röskva.

Minus the goats, Thor, Loki, and the two children continue east until they arrive at a vast forest in Jötunheimr.

Skrýmir awakes after each attempt, only to say that he detected an acorn falling on his head or that he wonders if bits of tree from the branches above have fallen on top of him.

Skrýmir gives them advice; if they are going to be cocky at the castle of Útgarðr it would be better for them to turn back now, for Útgarða-Loki's men there won't put up with it.

Skrýmir throws his knapsack onto his back and abruptly goes into the forest and "there is no report that the Æsir expressed hope for a happy reunion".

Thor agrees to lift a large, gray cat in the hall but finds that it arches his back no matter what he does, and that he can only raise a single paw.

Útgarða-Loki reveals that Loki had actually competed against wildfire itself, consuming all in its path (Logi, Old Norse "flame"); Þjálfi had raced against thought, always faster than action (Hugi, Old Norse "thought"); Thor's drinking horn had actually reached to the ocean and with his drinks he lowered the ocean level (resulting in tides).

[16] In the Prose Edda book Skáldskaparmál (chapter 4), a list of ways of referring to Thor is provided, including "lord of Þjálfi and Röskva".

In the same chapter, a quote from Þórsdrápa by the 10th century skald Eilífr Goðrúnarson is provided that refers to Þjálfi as "Röskva's brother".

In the poem fragment, Þjálfi stands enraged, Thor lands a winning blow on his target, and the two feel no fear.

[17] Þjálfi and Röskva are two major characters in the Danish Valhalla comics series, and the animated feature based on it.

Roskva and Thialfi (Alfi) appear as major characters in the junior novel The Sleeping Army by author Francesca Simon.