Why do you sometimes get to hear the sound of the mockingbird from Tribem of panem in Minecraft?

I regularly play minecraft in my single player world. I have heard the sound of the mockingbird from Tribute from panem a couple of times, but I do not know what that means. The sound came for example when I defeated a phantom or when I summoned the Wither…

Because Minecraft is a breeze and sucked out

Game rather Fortnite is much better than Minecraft

I just rinse Minecraft out fun it's still fun even if it's "out of date" and fortnite is even more hobby-less… Play Rainbow six wins