boated has some unique death mechanics.
When you die, you keep only your armor and whatever is in your hotbar, and a percentage of your XP. You also lose a significant amount of durability on your items. The items that you drop (your main inventory) go to a Gravestone which you can recover. Other players can loot this Gravestone.
You can die to natural causes (i.e. mobs). Other players can also kill you if you have PvP Flagging enabled with the /pvp Flag on/off command or if you died in a designated PvP zone.