#1 Hacked Clients [or Modified Clients]
All types of modified clients that deviate gameplay functionally in any way from the original Terraria client is forbidden; this also includes using 3rd party programs, such as Inventory Editors, to modify your character to possess impossibilities. However, texture packs are exempt*. Warnings may be given; however, due to the nature of the people using these clients, warnings may not be required. In cases where this negatively affects other players, to a degree of selfishness, then the ban may not be appealed.
People using any Modifications for PvP Advantages are deemed worse. Therefore, they should not be warned and instead banned.