Having pets in games - helps with player immersion

Role playing games are only successful as long as the player cares about their character and the world they are inhabiting. One way designers get players investing in the world is by giving them responsibility in that world. By giving players pets in game it gives the player one more thing to care about. These pets purpose in game can vary from cosmetic to being an actual participant in mechanics of the game.

Example: Firewatch Turt Reynolds

In Firewatch you can find a turtle in the wild. You are not looking for it and there is not a marker to lead you to it. The designer put it in the game just for fun. As soon as you find it you get to give it a name. it doesn't do anything but look at you. This turtle was a great design decision because it gave you a companion in this lonely game. It is also very inexpensive as far as design goes. There were a few audio files related to the turtle but its impact to the game far exceeds its cost.

Example: Fallout 4

Fallout 4 is also a very lonely game. There is a robot around that you can talk to but it's not the same as having a pet dog. Having the dog as your companion not only enhances the game and makes you feel less lonely playing it but the dog also helps you get through some of the more difficult parts of the game.

Example: Monster Hunter 3

In Monster Hunter, there are increasing choices of pets such as "Felyne" and "Shakalaka" as the player goes on the quest. The player can give them names, change costumes, do some casual activities like fishing with pets, and the pets also join the battle to help the player. There is also a cute pet pig existing in all Monster Hunter series. The pig doesn't have any functions but allowing the player to hug or carry around. These pets create strong bond between the game and the player. Players consider them as important partners and feel responsible to check their status and to play with them even they are not playing the major quests.

Example: Sims 3

In Sims 3, players are offered pets. Pets are the part of household and hold importance in terms of missions and checkpoints. Pets provide various experience points and allow player to perform activities like 'Take a Walk', 'Feed' and 'Pet Me'. These activities causes player immersion and player has to take responsibility of the pet in the game. Game offers a huge variety of animals as pets and also allow players to exchange them. This creates a community feeling among the players.

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Example: Fable 2

In Fable 2, the player has a pet dog following them through the entirety of the game. This dog acts as a companion in battle as well as in social interactions and also can help the player find items or simply act as stress relief by playing. This dog becomes a key element in the story of the game as the dog sacrifices itself for the player, acting as a factor in the player's final decision in the culmination of the plot on who to save - the masses, their family, or their dog. The presence of the dog in and throughout the game can add more weight to the player's decision and their immersion in the story as a whole.