The Moon Caller's Staff does not have an actual crafting recipe. Instead, one must place a Star Caller's Staff on a Moon Stone during a Full Moon, after which it will immediately start turning into a Moon Caller's Staff, but also start spawning multiple Werepigs and Hounds that will automatically target the base and attempt to destroy it, in order to stop the progress.
Haunting a Moon Caller's Staff has a chance to activate it. Haunting a Polar Light will extinguish it.
A single Moon Caller's Staff can keep players cool through about 6 Summers at the cost of sanity. This, along with the fact that it's portable, makes the Moon Caller's staff a great asset to players during summer.
A Moon Caller's Staff placed in the Moon Stone will create a permanent Polar Light. This will not decrease the staff's durability.
Care should be taken around the Polar Light, as it can easily cause freezing, even in Summer.