Godsire is one of those cards players keep asking about. Here is, in plain words, what its official text says, the rulings published by Wizards of the Coast, and the combos players actually run.

Official card text

Vigilance : Create an 8/8 Beast creature token that's red, green, and white.

How it works : Godsire

Original English text — Wizards of the Coast / Scryfall

No additional ruling has been published for this card.

Popular combos

Real combos played by the community, sorted by popularity.

#1
Thornbite Staff + Ashnod's Altar + Godsire
Infinite colorless manaInfinite death triggersInfinite creature ETBInfinite creature LTB
1Activate Godsire by tapping it, creating a creature token.
2Activate Ashnod's Altar by sacrificing the creature token.
3When the creature token dies, Godsire triggers due to its ability granted to it by Thornbite Staff, untapping Godsire.
4Repeat.

#1
Thornbite Staff + Ashnod's Altar + Godsire
Infinite colorless manaInfinite death triggersInfinite creature ETBInfinite creature LTB
1Activate Godsire by tapping it, creating a creature token.
2Activate Ashnod's Altar by sacrificing the creature token.
3When the creature token dies, Godsire triggers due to its ability granted to it by Thornbite Staff, untapping Godsire.
4Repeat.

#2
Thornbite Staff + Goblin Bombardment + Godsire
Infinite damageInfinite death triggersInfinite creature ETBInfinite creature LTB
1Activate Godsire by tapping it, creating a creature token.
2Activate Goblin Bombardment by sacrificing the creature token.
3When the creature token dies, Godsire triggers due to its ability granted to it by Thornbite Staff, untapping Godsire.
4Resolve the Goblin Bombardment ability, dealing 1 damage to any target
5Repeat.

#3
Thornbite Staff + Phyrexian Altar + Godsire
Infinite colored manaInfinite death triggersInfinite creature ETBInfinite creature LTB
1Activate Godsire by tapping it, creating a creature token.
2Activate Phyrexian Altar by sacrificing the creature token.
3When the creature token dies, Godsire triggers due to its ability granted to it by Thornbite Staff, untapping Godsire.
4Repeat.

#4
Thornbite Staff + Blasting Station + Godsire
Infinite creature ETBInfinite creature LTBInfinite creature sacrifice triggersInfinite damage
1Activate Godsire by tapping it, creating a creature token.
2When the creature token enters, Blasting Station triggers, untapping Blasting Station.
3Activate Blasting Station by tapping it and sacrificing the creature token.
4When the creature token dies, Godsire triggers due to its ability granted to it by Thornbite Staff, untapping Godsire.
5Resolve the Blasting Station ability, dealing 1 damage to any target
6Repeat.

#5
Intruder Alarm + Godsire
Infinite creature tokensInfinite mana creatures you control can produceInfinite untap of creaturesInfinite creature ETB
1Tap Godsire to create an 8/8 beast token.
2When the token ETBs, Intruder Alarm triggers, untapping all creatures.
3Repeat for infinite tokens.

#5
Intruder Alarm + Godsire
Infinite creature tokensInfinite mana creatures you control can produceInfinite untap of creaturesInfinite creature ETB
1Tap Godsire to create an 8/8 beast token.
2When the token ETBs, Intruder Alarm triggers, untapping all creatures.
3Repeat for infinite tokens.

#6
Thornbite Staff + Altar of Dementia + Godsire
Infinite death triggersInfinite creature ETBInfinite creature LTBInfinite mill
1Activate Godsire by tapping it, creating a creature token.
2Activate Altar of Dementia by sacrificing the creature token.
3When the creature token dies, Godsire triggers due to its ability granted to it by Thornbite Staff, untapping Godsire.
4Resolve the Altar of Dementia ability, causing a player to mill card(s)
5Repeat.

#7
Thornbite Staff + Spawning Pit + Godsire
Infinite charge counters on a permanentInfinite creature ETBInfinite creature LTBInfinite creature sacrifice triggers
1Activate Godsire by tapping it, creating a creature token.
2Activate Spawning Pit by sacrificing the creature token.
3When the creature token dies, Godsire triggers due to its ability granted to it by Thornbite Staff, untapping Godsire.
4Resolve the Spawning Pit ability, putting a charge counter on Spawning Pit
5Repeat.

#8
Thornbite Staff + Thermopod + Godsire
Infinite death triggersInfinite creature ETBInfinite creature LTBInfinite red mana
1Activate Godsire by tapping it, creating a creature token.
2Activate Thermopod by sacrificing the creature token.
3When the creature token dies, Godsire triggers due to its ability granted to it by Thornbite Staff, untapping Godsire.
4Repeat.

Interactions with other cards

These cards' text mentions Godsire.

Behemoth's Herald

{2}{G}, {T}, Sacrifice a red creature, a green creature, and a white creature: Search your library for a card named Godsire, put it onto the battlefield, then shuffle.