Calendar

In the aftermath of the Worldfire, existence nearly collapsed. Millennia of Chak-Tha's mantle as god of war drove her mad, crumbling continents under the weight of her corrupted soldiers and baking the universal constants in cosmic fire. Stewardship of reality became an immediate priority. Debauched Rennek and Hurak were chased to the furthest planar cavities as soon as their bloodthirst outstripped Chak-Tha's capture. Asmodeus retired with Chak-Tha in chains, escorting her solemnly to the deepest pit. Sliros, heartsick over the death of his brothers and having raised his hand against his only sister, numbly left the heavens to walk the Skylands in subtlety from that day forth. The mantle of god of war would never be used again, Chak-Tha's domains would be divided amongst the surviving gods. While the exact details of the agreement between the gods remain one of the great mysteries of the Skylands, ten of the gods volunteered to monitor the world, each taking a turn lasting thirty days. Each of these gods influences their month during their tenure.

Ten Months
Spring

Ooskavion: For wresting partial control of war from Ansilvund, Ooska was given first choice of when and how she would watch the world. Her month is the rebirth, a time of storms and thunder as the seasons change and warm currents of the roil settle after the long winter cold. While in the month of Ooskavion, heroes receive +4 to initiative checks, all casters receive a +1 to the caster level  and DC of all lightning spells, and once per day anyone can reroll a reflex save, taking the second result even if it is worse.

Tull: Tullerie's is a time of thaw, a time of harvest and bounty from the seas and lakes. The waters yield to living creatures. Everything from strong drink, to potions, to poisons increases in potency. Everyone receives a +5 to swim checks, there's 20% chance that any consumed liquid is empowered or it's save DC is increased by two, and all spell casters receive a +1 to the caster level and DC of water spells.

Maril: Mariona closes spring by protecting new life. Warm days, blue skies, gentle breezes, and fair weather peak during Maril, weakening the resolve of even the most violent. Her breath fills the world with positive energy. Everyone receives a +5 to diplomacy checks, 1/day healing you receive is empowered, and the AC bonus from Full Defense is increased by 4.

Summer

Pholantyre: The blazing heat reaches it's zenith, and the stars in the night sky become their most radiant. Those that dwell in shadow find small refuge as the bright light of Phol-Phoram shelters deception the least. Everyone receives +5 to sense motive checks, 1/day anyone can roll twice and take the higher on a will save, and all spell casters receive a +1 bonus to the DC and caster level of spells with the good descriptor.

Koronith:  The forests thicken with greenery and game. Korossos watches over young animals as they make their first forages and hunts. Those that respect his animals will have their sympathy, or be sped along their way. Everyone receives a +5 to handle animal checks, 1/day when using a summon spell to summon an animal you can summon an animal as a standard action rather than 1 round, and travel time through natural surroundings is halved.

Esthya: Esther marshals the currents in the roil between islands, keeping the winds from spiraling out of control as summer dwindles. While she tunes the wind for another year gravity is weaker and her presence guides all who fly. Everyone receives +5 to fly checks or checks made to fly an airship, falling damage is halved, and all air and wind spells are cast at +1 caster level

Fall

Harost: The leaves turn, all must return to the earth, either to become the earth or to sleep like seeds. Harosh prepares the land for the changes to come at the first chill. The bounty of the earth opens to those who need it easing the preparation of the industrious. Everyone receives +5 to craft checks, once per day on a random loot drop you can roll twice and take the higher, everyone receives  a +1 bonus to the caster level and DC of earth and acid spells.

Laredor: Laredos restitches the tapestry of fate, still creaking with the strain and burns left from Chak-Tha's fire. His close presence influences practicality, the strength of a community that puts preparation for winter before profit, and premonitions become more potent. Everyone receives +5 to appraise checks, 1/day any spell that answers questions allows an additional question to be answered, and anyone targeted or affected by a spell or effect that chooses it's consequences randomly receives an extra roll and can choose the second effect instead.

Winter

Amadius: Amadan chose the first month of winter as released roil spirits fed off days of ice, infirmity, and death. His close proximity to the Skylands weakens the undead and empowers those that fight them. Everyone gains a +5 to knowledge religion checks, mundane weapons and attacks are treated as magical for the purposes of striking incorporeal undead, and 1/day you can spontaneously affect a spell with the Threnodic or Thanatopic metamagic feat without either knowing the feat or increasing the caster level.

Kyroph: With all the problems that build up over a year, there's never enough time for the gods to finish the work of fixing reality. That's when Kyrophius comes in to cover up those pesky serious problems with reality with cheap patch jobs that look great but don't really fix anything. It gets pretty cold outside, you should probably just stay in and not check what that noise was, it's really foggy and hard to see anyway. Everyone gets a +5 bonus to bluff checks, 1/day characters can roll twice and take the higher on a disable device check, and everyone must roll twice and take the lower to disbelieve illusion spells.

Shifting Seasons
Despite Laredos' best efforts, time has never run on schedule since the Worldfire. Months that end early or go late allow for festival weeks and holidays. But the unpredictable month structure sometimes causes an absentee gap between the time that one god departs and another god arrives. Younger gods like Balthazar or Imaunte often step up during these times to have festival weeks, other times such openings come for malevolent opportunistic influences like Rennek and Hurak to seize control punctuating their time with plague and destruction.

Some scholar's scoff at the explaination for the unique properties of the seasons as superstition, assigning deific influence to account for random side effects of living above the chaotic roil. However, recent translations from ancient ruins excavated by an Institute of Ascension expedition testify that the year was once much longer, an entire month belonged to Chak-Tha in her ancient form, and  her calamity was powerful enough to shorten the year.