When Dakmor Salvage enters, Zendikar's Roil and Kodama trigger.
Resolve the Kodama trigger, choosing to put nothing onto the battlefield.
Holding priority, activate Coastal Hornclaw by sacrificing Dakmor Salvage.
The Gitrog Monster's second ability triggers, causing you to mill two cards and return Dakmor Salvage from your graveyard to your hand.
If a land was milled this way, The Gitrog Monster's second ability triggers, causing you to draw a card.
Resolve the Coastal Hornclaw ability
Resolve the Zendikar's Roil trigger, creating a token.
When the token enters the battlefield, Kodama triggers, putting Dakmor Salvage from your hand onto the battlefield.
When Dakmor Salvage enters the battlefield, Zendikar's Roil triggers.
Repeat from step 4.
This intricate loop transforms a humble land drop into an endless cycle of creation and dredging by using Coastal Hornclaw as a sacrifice outlet to feed The Gitrog Monster's replacement effects and draw triggers. As Zendikar's Roil pumps out Elemental tokens upon each landfall, Kodama of the East Tree notices those creatures entering the battlefield and immediately puts Dakmor Salvage right back into play from your hand. This constant recycling of Dakmor Salvage fuels both The Gitrog Monster's card-drawing engine and an overwhelming wave of triggers, creating an unstoppable cascade of value.