The visual trickery that turns hockey rinks into lakes of fire

Wired:

Pre-game presentations have long been excuses to trot out special effects. Indoor pyrotechnics, giant inflatable helmets, live wild animals running the field, and bone-rattling sound systems have been around for years.Turning a hockey rink into a lake of fire? That’s new.

The tech behind all of this is pretty cool but it seems like pointless eye candy to me.