Activate Scaretiller by tapping it, targeting Cacophodon.
Scaretiller triggers, returning Brokers Hideout from your graveyard to the battlefield tapped.
Brokers Hideout enters the battlefield, triggering itself and Roaring Earth.
Resolve the Roaring Earth trigger, putting a +1/+1 counter on Cacophodon.
Resolve the Brokers Hideout trigger, causing you to sacrifice it and search your library for a basic Plains, Island or Forest and put it onto the battlefield tapped.
If you put a land onto the battlefield this way, Roaring Earth triggers, putting a +1/+1 counter on a creature you control.
Resolve the Scaretiller ability from step 1, dealing 1 damage to Cacophodon.
Cacophodon triggers, untapping Scaretiller.
Repeat.
Results
Infinite +1/+1 counters on Cacophodon.
Infinite landfall triggers.
Put all basic Islands, Forests, and Plains from your library onto the battlefield.