Likes

Every monster has at least four different things that they like. For every unique object that they like that's placed near them, that monster's happiness will increase by 25%. Placing two of the same item near a monster will still only increase happiness by 25%. How quickly monsters earn coins is based on their Happiness.

Normally, for something to increase a monster's happiness, the two objects must be placed side by side. However, purchasing a Unity Tree from the market (available at level 16) will allow you place decorations and monsters anywhere you like on islands, including into Storage or a Hotel, without affecting the monster's happiness level.

This list makes reaching 100% happiness a cinch!

Some likes only work on certain islands. See Monster Likes for a list of each monster's likes, sorted by island. See Decoration Likes for a list of decorations that are liked by each monster.