This is a idea I had to link the terraform aspects of two seemingly unlinked factions like ST and FS. Each one of the spirits is a theme enabler that turns a kind of terrain into another related to the faction. Spirit of Spring: Race: Spirit, Class: Demi-God, Deck limit: 1, Faction: FS 0 DMG 6 SPD 1 RNG 0 DEF 45 HP Abilities: Ethereal Voice of the Spring : When Ice or Snow would be created by frendly sources, water is created instead. Orb of Rain: Champions within 4 spaces have Trail: Water. If the affected champion is friendly, it also gains Amphibious Growth Cleansing Aura Preordained Path 1: Tidal wave; water vortex Path 2: High tide; Water Veil Spirit of Winter: Race: Spirit, Class: Demi-God, Deck limit: 1, Faction: ST 0 DMG 6 SPD 1 RNG 0 DEF 45 HP Abilities: Ethereal Voice of the Winter : When water or vegetation would be created by frendly sources, ice or snow are created respectively instead. Orb of Frostfall: Champions within 4 spaces have Trail: Snow. If the affected champion is friendly, it also gains Arctic. Crystallize Freeing Aura Preordained Path 1: Snow Blast, Arctic Bolt. Path 2: Ice front; Ice Veil
how about KF? Spirit of Summer: Race: Spirit, Class: Demi-God, Deck limit: 1, Faction: KF 0 DMG 6 SPD 1 RNG 0 DEF 45 HP Abilities: Ethereal Voice of the Summer : When Water and ice/snow would be created by opposing sources, vegetation is created instead. Orb of Vegetation: Champions within 4 spaces have Trail: Vegetation. If the affected champion is friendly, it also gains Brushwalker Growth 3 Cleansing Aura Preordained Path 1: ; Healing breath 1 , Healing breath 2 Path 2: Spontaneous growth; Vegetation Veil
That's more a code thing than a design thing. It's not a intended interaction for obvious antisinergetic reasons so in whatever way it behaves isn't too important.