When Junk Diver enters the battlefield, The Sibsig Ceremony triggers, destroying Junk Diver and creating a 2/2 Zombie Druid creature token.
When Junk Diver dies, it triggers, returning Workshop Assistant from your graveyard to your hand.
Cast Workshop Assistant by paying 0.
When Workshop Assistant enters the battlefield, The Sibsig Ceremony triggers, destroying Workshop Assistant and creating a 2/2 Zombie Druid creature token.
When Workshop Assistant dies, it triggers, returning Junk Diver from your graveyard to your hand.
Repeat.
This ingenious loop relies on a clever cost-reduction engine to cast artifacts for free while recycling them endlessly through the graveyard. By tapping Ezzaroot Channeler to gain life, you boost its passive ability to reduce creature spell costs by 2, which teams up with The Sibsig Ceremony to slash a further 2 generic mana off your creature spells—making artifacts like Junk Diver and Workshop Assistant cost a mere {0} to cast. Once cast, The Sibsig Ceremony immediately destroys the newly arrived creature upon entry, sending it straight to the graveyard. That death trigger lets Junk Diver and Workshop Assistant retrieve each other from the graveyard in an endless, mutually beneficial cycle that floods the board with an army of 2/2 Zombie Druid tokens.