Merge Christmas is a merge game in the Suika subcategory. The player merges white snowballs marked with Christmas-themed icons to create ever-larger snowballs until they reach a final evolution stage. They also attempt to earn a high score.
The snowballs display common related icons, such as gingerbread men, Christmas trees, snowmen, reindeer, Santa Claus, elves, toy bears, penguins, polar bears and holly berries and leaves. The ultimate evolution is a snowball that features Santa wearing sunglasses.
Against a backdrop of a jolly Santa jumping off a roof, the player drops the snowballs into a box-like container created with a glowing outline. They don't receive an aiming line to help them. Although they can only drop a single snowball into the box at a time, they can check a preview of the next available one in the upper-right area to plan their drops better. They also receive a circular holiday tray in the upper-left corner that displays the evolution of merges.
If the player allows the snowballs to stack too high in the container, they risk losing the game. The container permits momentary stacking above a dashed horizontal penalty line, but the player only receives seconds to correct their mistake. Additionally, the game doesn't use any color or flashing warning to alert the player that they've allowed the balls to stack too high.
Merge Christmas has a booster button in the upper-right area that helps prevent this issue from ever becoming a problem. The player can use a brush to sweep away any one snowball. They merely need to watch advertisements to access the tool.
