Does Teemo's, Cassiopeia's, and Singed's poison stack, or does the stronger poison tack over, or is it the last one how hit the enemy with poison get it, or what?

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4 Answers

It all stacks, so the champ will take damage from each skill used on him.

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Yes, the damage from the poisons stack, and for Cassiopeia's abilities any poison counts for the additional effect.

Source:

All damage spells stack. Ignite's damage stacks but it does not stack the 50% healing reduction, a person can only be at 50% healing reduction no matter how many ignites are on you.

Actually teemo's "e" does not stack according to lol wiki: "This poison will not stack but the duration will be refreshed with every subsequent attack."

There used to be a bug where Teemo attacked so fast that he never got the poison to activate. This was fixed in the Hecarim/Varus Skills and Stats + Patch Changes in April 2012.

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