Madness Steve himself actually wasn't the creator of the cult. The creators of it were those who hated everything about existence. The names of those leaders as well as when the cult was created were lost to time.
Madness Steve took notice and approved the cult's. The leaders of the cult willingly offered Madness to torture them to death to show their loyalty. Madness didn't, and said he'd spare them, but the leaders had to step down and continue showing loyalty. The leaders willingly complied with the demands, and when Madness took control, that was when the cult was formally recognised. Beings across all realities and dimensions started joining. The cult grew so large that they were even considered a race. The cult is everywhere through time, and the size of the cult is infinite.
The power and hax of each cult member were weaker than whatever Stage Madness Steve's False Form's at. If Madness is out of the Madness Dimension completely, they become omnipotent and omnipresent.
While everyone would be tortured for an eternity, Madness spares his followers and stated to them they'd live in an eternal paradise in his new everything, once the old everything was removed from existence. Madness also made it so his False Form doesn't get power from his followers. Madness respected his followers, and he gave them free will. He just expects the cult to show loyalty to him back in return.
Those who wanted to join had to torture everyone they considered themselves close to.
They had to keep doing so until they passed out, and then they could kill them. To impress Madness, some waited for the tortured to wake up to begin torturing them again, and repeated until those being tortured wouldn't keep waking up. If people did that, cult members would become aware and would protect you while you continued the torture. Once you were done, you had to let cult members torture you to death with what you fear the most. Once that was over, Madness himself would welcome you into his cult.Those who get into the cult become completely black. They get turned into the shape of a steve, then they're given armour and spear. The armour and spears enhance the abilities the cult members already had.
All cult members also have 4th wall awareness. This is because of my server called "The Cult of Madness Steve." You can also join it (please don't torture people to join the Discord).
All cult members were practically immortal. Whenever one got destroyed, Madness would just bring them back with his False Form. If Madness is outside the Madness Dimension completely, it wouldn't matter, because as all cult members become omnipotent and omnipresent, they can't be destroyed anyways.
The cult doesn't take divergents lightly. Anyone who stopped showing loyalty to Madness was reverted back to who they were. Then those divergents were tortured by the whole cult, at the cult's free will, which had no bounds.
If Madness Steve was reformed back to Calmness Steve, the cult's power reduces massively. Although the cult would remain to exist, their base power is reduced to just Stage 1. The cult also loses their immortality, as Calmness certainly won't bring them back. In the event Calmness Steve became Madness Steve again, the cult would regain the immortality and they'd be able to get more power. It does also depend on whether Calmness gets successfully escorted to the Madness Dimension before he becomes Madness again, as the transformation between Calmness to Madness as well as Madness to Calmness isn't instant.