To tack on to what @EdibleGasMask said:
Rosary peas do contain a highly toxic compound called abrin, which is incredibly potent, more so than ricin. But here's the thing: viability as a method is questionable and dangerous in ways people don't always realise.
Yes, abrin can be lethal. But the seed's outer coating is very hard, and if swallowed whole, it often just passes through the body without releasing any toxin. That's why many accidental ingestions don't result in death. To release abrin, the seeds have to be chewed, ground, or otherwise processed, which brings huge risks: abrin exposure through mucous membranes, inhalation during grinding, or accidental contact with open skin wounds can result in organ failure, intense pain, and a slow, violent death that isn't quick, peaceful, or guaranteed. It's not a "pass gently in the night" sort of thing. It's often vomiting, bloody diarrhoea, seizures, multiorgan collapse. Days of suffering.
And the dose isn't reliable. Even small variations in seed size or preparation method change the amount of toxin. That makes it not just painful, but unpredictable so much so you could end up permanently damaged, hospitalised, or dead days later in agony, with no certainty of outcome.
I know the allure of something natural or local can seem appealing, but rosary peas are not a safe method. If anything, they're one of the most dangerous to even attempt preparing. The risk of accidental harm to others (pets, people who handle the remains, the environment) is also high.
