How can you create a combo with Yurlok of Scorch Thrash, Leyline of Abundance, Umbral Mantle?
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[START OF COMBO]This combo can be formed with Yurlok of Scorch Thrash, Leyline of Abundance, Umbral Mantle

Color identity: BRG
Mana cost: {1}
Steps:
  1. Activate Yurlok of Scorch Thrash by paying {1} and tapping it, causing you to add {B}{R}{G}{G} and each opponent to add {B}{R}{G}.
  2. Activate Yurlok of Scorch Thrash by paying {3} and untapping it, causing itself to get +2/+2 until end of turn.
  3. Repeat an arbitrarily large amount of times.
  4. Move to your next step or phase, causing each opponent to lose life equal to the amount of unspent mana in their mana pool.[END OF COMBO STEPS]

Result:
  - Infinite black mana for opponents
  - Infinite green mana for opponents
  - Infinite lifeloss
  - Infinitely large Yurlok until end of turn
  - Infinite red mana for opponents[END OF COMBO RESULT][END OF COMBO]

Other prerequisites:
  - All permanants must be on the battlefield
  - Umbral Mantle attached to Yurlok of Scorch Thrash.
  - Yurlok of Scorch Thrash does not have summoning sickness.
[END OF COMBO PREREQUISITES]
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