Aside from SLAs, skills & mental stats, I think the formless states will be pretty similar for all of the SotLs
Colossal fey
Senses: all-around vision, darkvision, low-light vision; Listen +30, Spot +30
Languages: telepathy within lands
Immune: all attacks (see below)
Speed: 0 ft. (0 squares)
Space: [extent of land]; Reach —
Special Actions: elemental manifestation
Spell-like Abilities (CL 21th):
Abilities: Str —, Dex —, Con —, Int ??, Wis ??, Cha ??
SQ: Diffuse & Formless
Skills:
All-Around Vision (Ex) Because a Spirit of the Land in its formless state is composed of the terrain surrounding it, it can see in any direction, bestowing a +4 racial bonus on Spot and Search checks.
Diffuse and formless (Su) Because a Spirit of the Land is normally composed of the terrain surrounding it, a Spirit of the Land cannot be attacked directly unless it manifests its elemental form. In its normal formless and diffuse state, a Spirit of the Land cannot be directly attacked, although it will suffer and die if its land is destroyed.
Elemental Manifestation (Su) At will, a Spirit of the Land can assume a corporeal form, made from the predominant elements of its land. Each Spirit of the Land has specific and unique elemental manifestation, and each of these is treated like a separate monster. See ―Spirit of the Land (Elemental Manifestation).‖ Should a Spirit of the Land‘s elemental manifestation be destroyed, the physical dissipates and the Spirit must wait 24 hours before it can manifest itself again, or use any of its spell-like abilities, including the granting of spells.
Wild Empathy (Ex) This ability works like the druid‘s wild empathy class feature, except that the Spirit has a +6 racial bonus on the check.