Passive creatures do not attack the player or other creatures, but provide useful resources when killed (or harvested). Sometimes, these creatures seem to be difficult to kill, but using the right strategy will make killing them much easier.
Crow[]
Every now and then, a crow will land, which will make it an easy target. However, they will quickly fly away when approached, so it is advised to kill them using a ranged weapon such as a bow or a throwing spear.
As suggested by in-game tips and players observations, crows tend to land more often during the night and during storms. These are good times to farm for feathers.
Deer[]
Locating a deer is relatively simple as they will often emit a whimpering call when nearby. Once located, it is advised is to crouch and keep ample distance from the deer. Use ranged weapons such as a bow to quietly kill them before they become alerted.
Deer who are alerted by players and other hostile creatures will attempt to flee until they are no longer within close range of being attacked. If alerted, the player can wait a short while before the deer calms and stops trotting away.
Fish[]
Fish can be caught by hand or using a Fishing rod and Fishing bait which can be purchased from the trader.
You can obtain Raw fish by grabbing the fish if it above the water. When catching fish by hand, stand still in shallow water and they will slowly approach. Move your cross hair over the fish. It is also possible to chase fish into a shallow or narrow body of water to more easily catch them.
Fish come in different sizes and give different amounts of raw fish. Tuna give the most raw fish at 4 pieces. Tuna are found further out from shore and move much faster than other fish.
Gull[]
Every now and then, a gull will land, which will make it an easy target. However, they will quickly fly away when approached, so it is advised to kill them using a ranged weapon such as a bow or a throwing spear. Abyssal harpoons are very good as they don't need to be picked up like the spear
As suggested by in-game tips and players observations, gulls tend to land more often during the night and during storms. These are good times to farm for feathers.
Leviathan[]
Each one of a Leviathan's 21 Abyssal barnacles have 40 Health and attacking any of them has a chance to trigger the submerge event even if the barnacle isn't fully destroyed. Try to keep your stamina high at all times and make sure you parked the boat with the ladder-side facing the the Leviathan, since if the Leviathan submerges while you are still on it, you will need to swim to your boat and climb onboard it in order to survive.
Higher pickaxe skill and better pickaxes allow mining barnacles with less hits which allows getting more Chitin before the sinking gets triggered. Positioning also matters. If there is too much space between the player and the barnacle, the damage will be split between the barnacle and the invulnerable Leviathan shell.
Lavaiathan[]
Higher pickaxe skill and better pickaxes allow mining flametal nodes with less hits which allows getting more flametal ore before the sinking gets triggered. Positioning also matters. Alternatively, a player may wish to risk the strategy of employing a battering ram on the ore vein if the lavaiathan is close enough to non-lava terrain in order to maximize the number of ore nodes broken at ground level.
Hare[]
Hares behave similarly to deer, but due to the limited visibility of the Mistlands, it is difficult to spot hares from afar before alerting them. For this reason, the Arbalest can be a useful weapon for hunting them, thanks to its ability to instantly fire a loaded bolt.