How do I kill with poison?

There is some point in the story where you receive poison to kill someone, but every time I click on the poison I die. I tried shaking the dusts over the papers or using the seal with them, but no luck.

How do I apply the poison on their passports without dying??


Solution 1:

Here's a video that shows you how to do it:

Basically, you have to open the poison card 3 times (don't touch the poison).

You open the card by clicking on the arrows 3 times.

Here's also an image:

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