How about this: Isolde is not a Deva; she is still an Angel, though she physically resembles a Human (and has lost any ability to fly as a result). When she requested permission to hunt down the Gentleman Caller from her patron Deity, she was told that she would only be allowed to go to the Natural World if she became a Deva, embracing the never ending cycle of reincarnation. That was unacceptable to her, so during the Grand Conjunction Isolde flew into the Shadowfell and forced herself into one of the collapsing Domains of Dread, where she sensed the Gentleman Caller's power.Jester of the FoS wrote:Maybe. But there's the choice between changing the world for the mechanics or changing the mechanics to fit the world.The Pickled Punk wrote:IMO its the closest that a 4E version of Isolde can come to fitting into the older canon. The game mechanics and default assumptions of 4E are not the ones used in earlier editions. The goal shouldn't be "This has to be identical to what came before", it should be "How can we make this fit into the spirit of what came before?"Jester of the FoS wrote: It's not a great fit for canon, but acceptable.
Having Isolde become a high level deva keeps the 4e lore, as would having her be an eladrin from the Feywild.
The other option is retaining Isolde as an angel and having her appearance change, giving her a shapeshifting power.
A good update of a campaign setting is a compromise. Changing what works best changed (especially when the original flavour was a reflection or compromise for old rules) but trying to keep the original story when possible.
At that moment the Grand Conjunction collapsed, she found herself in the physical body of a human woman, naked, but for her divine greatsword. Accosted by brigands, she handily dispatched them, dressed in the clothes and armor of one of them, and then heard cries for help. The rest, as we know is history. Isolde discovered she retained much of her Angelic power, but that she also had a reality wrinkle causing the Twisting.
Devas on the other hand, despite their Immortal origins, would not have reality wrinkles. Perhaps it is because of the cycle of reincarnation they have devoted themselves to, perhaps it is due the length of time since they left the Astral Sea to wander the Natural World, or perhaps it is because the Dark Powers consider them beneath their notice (unlike Isolde who entered the Domains of Dread in violation of the Unspoken Pact).
This way we can eat our cake and still have it: Devas get to be a PC race, while Isolde remains a unique character, with powers far beyond those of a Deva (but not quite the same as those of the Angels in the Monster Manuals).