How do i make a weapon that poison?

I don't know if you're asking for the whole gun script, or just the poison damage part. Due to this, I will link a video for making a working gun and I will go over the poison script.

In the part off the script where it will deal damage, so if the bullet successfully hit a player it will need to loop through it 10 times, once for every second. You can do this by saying

for i = 1 , 10 do
end

This will loop 10 times. Now we need the damage part, so at the start off the script we will declare a number variable called "Damage". This is just to make it easier to change. We also need the Humanoid declared.

local Damage = 1
local Humanoid -- Declare the humanoid in a different part off the code, it depends how you scripted the gun system on where this will be.
-- Other gun code here
for i = 1 , 10 do
end
-- Other gun code here

Now we need to actually damage the player, we can do this by running Humanoid.Health -= Damage, this way it takes damage and if it will be an amount to kill them, it will ignore the forcefield. We can also call Humanoid:TakeDamage(Damage). This way the player can't take damage if they got attacked while having the force field. This is the way I will use it.

So now, our poison code will look something like this:

local Damage = 1
local Humanoid -- Declare the humanoid in a different part off the code, it depends how you scripted the gun system on where this will be.
-- Other gun code here
for i = 1 , 10 do
    Humanoid:TakeDamage(Damage)
end
-- Other gun code here

Finally, we need to add a wait(1). This is because it will instantly run this loop and deal the damage in one go. The final code should look like this:

local Damage = 1
local Humanoid -- Declare the humanoid in a different part off the code, it depends how you scripted the gun system on where this will be.
-- Other gun code here
for i = 1 , 10 do
    Humanoid:TakeDamage(Damage)
    wait(1)
end
-- Other gun code here

• YouTube link for making a working gun.

• This poison script is ran on the server