The phrase "playing tricks" can be replaced with a variety of synonyms, depending on the context and tone of the sentence. Some common options include: "pranking," "joking around," "teasing," "messing with," "pulling someone's leg," "trickery," "mischief," "deception," "gags," "silliness," "antics," and "shenanigans." While some of these words imply a harmless sense of fun, others suggest more deceitful or mischievous behavior. Choosing the right synonym is key to conveying the intended meaning and tone.