This addon has been abandoned and has transferred over to Skream. Skream has drastically improved upon the teams elements in this addon and has added many new elements. Skream will continue to be updated, this addon will not.
skript-teams
Your go-to Skript addon when it comes to handling Minecraft Teams.

This addon allows you to do the following:
Create Teams
Delete Teams
Add players and entities to teams
Remove players and entities from teams
Get & set different properties of the teams
Successfully remove all potion effects from players and entities
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