ROTMG is a PermaDeath game. This means that if your character dies, you cannot play as that character again. You lose all of that character's items, although your pet is unaffected, and you must start a new character at level 1.
The Vault can store items. If you die, you keep anything in your Vault. Many people use this advantage to save all expensive items.
- If you just started the game, when you first lose all of your Health Points, you will be greeted with a message that explains Permadeath to the Character, followed by warping his current character into the nexus.
- ROTMG is one of the Prime examples of doing Permadeath correctly. Other games that do this badly or insanely over powered cause you to lose EVERYTHING, including any structures, items (even in chests), and progress, and some times even the world that you make(Terraria).