The Gitrog, Ravenous Ride

Trample, haste
Whenever The Gitrog deals combat damage to a player, you may sacrifice a creature that saddled it this turn. If you do, draw X cards, then put up to X land cards from your hand onto the battlefield tapped, where X is the sacrificed creature's power.
Saddle 1

The Gitrog Monster

Deathtouch
At the beginning of your upkeep, sacrifice The Gitrog Monster unless you sacrifice a land.
You may play an additional land on each of your turns.
Whenever one or more land cards are put into your graveyard from anywhere, draw a card.

Thalia and The Gitrog Monster

First strike, deathtouch
You may play an additional land on each of your turns.
Creatures and nonbasic lands your opponents control enter tapped.
Whenever Thalia and The Gitrog Monster attacks, sacrifice a creature or land, then draw a card.

Gitrog, Horror of Zhava

Menace
At the beginning of each combat, if Gitrog, Horror of Zhava is untapped, any opponent may sacrifice a nontoken creature. If they do, tap Gitrog, Horror of Zhava, then seek a land card and put it onto the battlefield tapped.
Whenever a land enters under your control, it perpetually gains "{B}{G}, {T}, Sacrifice this land: Draw a card."