i need some plugins

i'm searching for some cool plugins with more or less this effects:
-missions/quests
-new bosses
-new weapons, maybe uncraftable, you can find them just in chests and by killing bosses
-new biomes and/or worlds

basically i'm playing with a friend of mine on i server i host, and we'd like to have this stuff in game to make it more funny and not boring... you can suggest other things obviously