The "Polar Undine" is an archetype of female WATER Fairy-Type Spirit monsters, created for use by Polari, an OC (originally named "Merag") daughter of and , ideated by the FanFiction.net authoress Durbe the Barian. It was conceived as a union of the deck themes of her parents, " s" and WATER Winged Beasts.
- Since immemorial times, the Polar Undines, coming from their icy home belonging to the North Polar Star, travel between worlds to protect other populations from the cold. They are usually kind and help everyone, but if someone disrespects them, or invades their protected territory, they will react with freezing wrath.
|Polar Undine||Inuit goddess|
|CXyz Goddess Aakuluu||A'akuluujjusi|
The "Polar Undines" are represented as apparently-benevolent young girls (except the two Xyz Monsters, who are fully grown women) with an ice sprite motif. They lack legs, having instead ghostly tails, and posses large and elaborate veil-like wings. The Main Deck members have their hair done in various variants of hairtails, tied by a band bearing the monster's own showflake symbol. They only wear big striped jackets with large sleeves.
All the members are named after Inuit goddesses, with the Xyz Monsters having the names of the most important two.
Besides the usual Spirit effects (they cannot be Special Summoned, and return to the hand at the end of the turn they are Normal Summoned or flipped face-up), each "Polar Undine" Main Deck monster has two effects. The first effect generically supports Spirit monsters, giving various searching and field-gathering advantages. The second one, instead, is an effect that is passed to the "Polar Undine" monster that curretly has it as an Xyz Material. This way, the archetype's Xyz Monsters serve to gather up various effects, functioning as multi-purpose powerhouses.
The "Polar Undines" are aided by a group of five Spells, the "Boreas" Cards. They refer to the group's homeworld, a fictional icy planet around the star Polaris, and four of its frozen landscapes, each thematically linked to one of the elemental Attributes (EARTH, FIRE, WATER, WIND).
While the Field Spell, "Boreas, Ice Spirit World of Polaris", supports extensively Spirit monsters (even combining the effects of various of their older support cards), the four Continuous Spell Cards work only with the "Polar Undines", giving them a variety of effects that help them to dominate the Duel. Additionally, the Field Spell can gain the effects of any one of the Continuous Spells once per either player's turn, in case the player didn't draw them or if they doesn't want to use up all of his Spell & Trap Zones, but this way the effect can only be used until the end of that turn.