One day, suddenly, over night, anybody who had a fursona or similar nonhuman alternate identity, woke up as such. But not only that, also anybody who didn't is gone with out a trace.
The principles of electromagnetism and thus electricity have been replaced by the laws of Mana, meaning that unless some one learns how to power technology with Magic, anything that has any form of electrical component won't work.
What ever caused this change decided to preserve people in life threatening situations. If they are on a boat or a plan, they will find themselves at their destinations. Also if someone was in a life treating situation they'd find themselves miraculously cured and/or saved
Along with people with people who where without a fursona, domesticated animals were not there if they lived with a family. Most other animals will remained so long as they didn't depend on specific humans for food.
The nature of any person's Digestive track would remain omnivorous.
The laws of magic is that, at any given location, there is a finite amount of Mana, the energy for using magic and magical abilities All loose mana that is not drawn within a living creature will have a certain disposition to the four main elements. Any living creature can with force of will gather it and by using force of will cause something to happen. What a person can manage varies from individual to individual After the spell is cast, the mana is released to the environment and is realigned to what ever the nature of the spell was cast.
As the relative value of any given elemental alignment in the environment rises, things start happening according to the element. An abundance of fire mana causes temperature to rise and fires to start. A lack of fire mana causes the temperature to drop and for fires to mysteriously go out. Too much water mana causes rain and eventually floods, were a lack can cause a drought. With enough earth mana, plants start to grow wildly and eventually earthquakes start, without enough of it, plants begin to wither and the ground slowly turns to sand. To much wind mana will make severe winds and perhaps even tornado's and lightning. Too little, and you will have air stop dead, being resistant to even being fanned to move.
All who make the change are given the abilities of their form, but it came at a price. If their strengths exceed a certain level, they begin to lose endurance as they gain more strength.
Some others also got changed, but for a totally different reason. These people changed because they lacked any humanity in either their mind or soul. These people where cutthroat ruthless beasts in reality and cared nothing about the qualities such as compassion that separates us from the animals. Their new form is simply the one that most closely matched their character. All those whom came due to being less than human can't use magic period. Instead all their physical prowess has improved at the cost of some mental ability. So they literally become beasts.
Before joining, everyone is going to have to make a back story for up until they enter the actual RP. I would Ideally want to make this as close to the reality as possible so that it's actually you who wakes up as one of your characters, but artistic liberties are permitted to make this more fun and anonymous, so location is mutable and so is what you have, just try to keep to your own personality.