The Dreaming cult
Dreaming cults emerge all over the word, brewing various dreaming elixirs and drugs that let their followers dream themselves into the Dreamlands. From there caravan of dreamers leave the crumbling dreamworld, taking along citizen of the Dreamlands. Some people manage to dream themselves differently while others distort their dreamself under the influence of hallucinogenic drugs. The cities were the cult take hold become quiet place as people fall sleep one after the others.
Some dreaming cults also become suicide cults as the dreamers plan to die mid-dream, out of belief of a stronger dream transfer or out of fear of having their dream journey interrupted by rivals who may attempt to wake them up to prevent their escape.
Dreamers can use their dream elixir to dream themselves into the pocket worlds they encounter.
Some wizards or technomancers guilds attempt to use a astral aleph to use as either the seed of a remade version of the world, or at least a record thereof. They attempt to connect themselves to a astral aleph to use the aleph to ‘focus’ on this world so others reading the aleph experience it.
Parallels here to computer uploading — you contract with someone on another world to build a copy of you via totalizing aleph-information, who believes that to be ‘you’. Different answers may apply in worlds with hermetic metaphysics. It's more a philosophical question of whether perceiving the thing, even perfectly, is the same as being present with the thing. To continue the 'uploading consciousness' comparison, duplication of the process by different 'end points' would lead to multiple perfect copies/transmissions.
Printed copies of people and things recorded from the dying world form caravans. Some people and things are printed with errors as the world get closer to it sunset. There is also rumor of aleph operators editing or hacking the transmitted data before printing it.
Each caravan carry a portable aleph recorder that let them beam copies of themselves into the aleph terminals that the Builders installed in pocket worlds. The Builders weaved a large network of aleph terminal around the pocket worlds that once formed their astral plains empire, but since the Builders left, most of these terminals are now offline or malfunctioning.
The Arks of Abzu
As the world is unmade, great arks (or ark-ologies) are constructed to sail the Sea of Chaos that the material world descends back into. Their shells must be hardened with the powers of Creation and Law to resist the unmaking, or be built from nonlocal materials so as to shield the interior from the unmaking.
The protective wards of some ark may breach during the voyage and chaos may infect some the ark's passengers and crew. There is also the danger of encountering raiding chaos ships.
While sailing the astral seas, the arks may emerge into pocket worlds. Since outside of the world, time doesn't really exist, they might emerge from the astral sea into an pocket-world after having experienced vast epochs in their own divergent timelines, or have been transformed by the experience of abyssal timelessness.
Cults form around charismatic guru and holy figures and popular astral travelers who entered a state of meditation that will soon let to the ascent of their consciousness into the astral plains and beyond.
Their followers latch themselves onto the spirit of these greater being as they ascends their consciousness. They unhook when they passes by the astral plains, just before their master ascend into the cosmic planes.
Karmic hitchhiking runs the risk of carrying bits of your ride along with you - sometimes there's enough to overpower you, and you're left as the fragment of a greater being.
The Milk Roads
A highway of translucent white star-stuff that appeared as the world began to sunset. Traveling the Milk Roads is a relatively safe methods, but crowded with caravans. Space and supplies at a premium.
Marching too long on the Milk Roads might lead one to decide it's better to live forever among the stars unthinking than to continue on to a new home. The risks of moving in large groups of desperate people go without saying.
Some people drink the milk of the road, if they survive their eyes become milky white, they spiritually connect to the roads and become starry guides. Starry guides are able to see the fainter milk trails that connect the pocket worlds together.