Putrid Goblin dies, triggering its persist ability and Golgari Germination.
Resolve the Putrid Goblin trigger, returning it from your graveyard to the battlefield with a -1/-1 counter and a vigilance counter on it.
Resolve the Golgari Germination trigger, creating a 1/1 Saproling creature token with a vigilance counter on it.
Activate Tayam by paying ({3} magic symbol) , removing both counters from Putrid Goblin and the counter from the Saproling token, causing yourself to mill three cards and allowing you to return a permanent card with mana value three or less from your graveyard to the battlefield.
Activate Ashnod's Altar by sacrificing the Saproling, adding ({C} magic symbol) ({C} magic symbol) .
Repeat.
Results
Infinite colorless mana.
Infinite creature tokens.
Infinite death triggers.
Infinite ETB.
Infinite LTB.
Infinite sacrifice triggers.
Infinite self-mill.
Put all permanents with a mana value of three or less from your library and graveyard onto the battlefield.