Dagger of Venom

[Booker Grimm]

Struggling with adding a Dagger Of Venom to my NPC action section. Can add the attack and damage, but can't add the ability to add the CON saving throw and Poison DMG to the victim.

Please help.

5e rules.

Cheers,

Dan

[Zacchaeus]

This is the wording needed:

[Booker Grimm]

Thanks Zacc.