This guide contains the lists of rewards that you can obtain when you kill certain monsters.
Note: you can only obtain an item from a monster if their level is no more than one level below yours.
Leather Cuisses
Leather Vest
Club
Light Buckler
Elixirs
Executioner Vest
Mammoth Cuirass
Twilight Cuirass
Linen Shirt
Leather Boots
Bronze Chest
Metal Chest
Executioner Cuisses
Mammoth Cuisses
Twilight Cuisses