The Unusualifier is a tool item that can be applied to a specific taunt. It is an upside-down top hat emitting an aura of fire, with a magic wand leaning on the left side of it and stars springing out of it. This item can be found as a bonus item from unboxing a Case. The speculated drop rate for an Unusualifier is 0.6 to 1 percent.
Using this tool on its specified taunt will give the taunt a random Unusual effect.