All methods that can succeed must include the cooperation from the herd in their own extermination.

A poison that immediately kills will be quickly routed.

It has to be a long and slow kill off to be successful.

However, if it takes too long they may build an immunity to the poison.

So it must, by necessity, kill fast enough such that they cannot build immunity but also slow enough that they not figure out it is poison.

Consider it by analogy.

Ants.

To kill a nest of ants you cannot simply kill the scouts and workers.

The queen is the source of your infestation, and so long as she lives their ranks will be replenished faster than you can blink.

So one must target the queen.

The queen, however, is safeguarded. Hidden and protected.

Therefore, a poison must be made to target the queen, not the workers. It must also dupe the queen as it too dupes the workers.

Ant poison works on this principle. You give the ants food to take back to the queen and unknowingly poison her.

Now, all that is required is to choose a poison.

Again, it has to work slowly, but not too slowly. It must also be undetectable as a poison.

As we have discovered, the best method is not to aim for death, but aim for starvation. Any siege requires attrition.

So, ant poison works as such -- it coats the intestines of the ants and their queen gradually, such that the more they eat the more they starve themselves of the nutrients. As they eat the sugary poison, they cannot fathom why it is they grow more and more hungry. Being plentiful, they eat more of the poison. Until...

Until the queen finally starves, a glutton for that which ultimately killed her.

That is the secret to poisoning the masses.

Give them exactly what they want, knowing what they want is also the source of their demise.

Feed them their vices, and lace it with your poison.

Feed them ideologies. Feed them drugs. Feed them entertainment. Feed them outrage. Feed them moral supremacy. Feed them promises. Feed them addictions.

Feed them exactly what they want.

Until they become one of the FED.

It is a poison not only working on the Body, but working on the Mind as well as the Soul.

Temptation.

Temptation itself is the penultimate poison of the ages.

The secret formula for culling the unkempt masses.

For aren't the ants not tempted to eat more of the poison, even if they somehow discover it is killing them? When starved, they say "just one more, and then I'll stop, I swear it!"

In that final moment, the delusion is complete, and you, the poisoner, now own the keys to their demise as well as salvation.