Lathiel, the Bounteous Dawn

Bracket

• B1 Exhibition — Not in the same deck as its two-card combo partner: Mayael's Aria
• B2 Core — Not in the same deck as its two-card combo partner: Mayael's Aria
• B3 Upgraded — Not in the same deck as its early two-card combo partner: Mayael's Aria
• B4 Optimized — allowed: No restriction beyond the banned list
• B5 cEDH — allowed: No restriction beyond the banned list

Why

• Two-card combo with Mayael's Aria (early with Mayael's Aria)

How Lotus Vault estimates a bracket

Bracket: Lotus Vault analysis, with Commander Spellbook flags

Combos

6 known combos, one of them two-card.

• Mayael's Aria + Lathiel, the Bounteous Dawn
  Produces: Win the game at the beginning of your next upkeep
  View on Commander Spellbook
• Lathiel, the Bounteous Dawn + Sage of Hours + Honden of Cleansing Fire
  Produces: Infinite turns, Lock
  View on Commander Spellbook
• Lathiel, the Bounteous Dawn + Sage of Hours + Celestial Force + Boon Reflection
  Produces: Infinite turns, Lock
  View on Commander Spellbook

Combos: Commander Spellbook

Rulings

• 2020-11-10 · Wizards of the Coast
  The triggered ability will consider the total amount of life you've gained that turn, not how your life total has changed. For example, if you start the turn at 10 life, then gain 5 life, and then lose 7 life, you'll distribute five +1/+1 counters, even though your life total is now lower than it was at the beginning of the turn.
• 2020-11-10 · Wizards of the Coast
  If some, but not all, of the creatures are illegal targets as the triggered ability tries to resolve, the original distribution of counters still applies and the counters that would have been put on illegal targets are lost. If all of the creatures are illegal targets, the ability won't resolve.
• 2020-11-10 · Wizards of the Coast
  Gaining more life in response to the triggered ability won't change how many counters will be distributed, nor will it change the distribution.
• 2020-11-10 · Wizards of the Coast
  You may choose no targets if you want. In that case, no +1/+1 counters are put on any creature.
• 2020-11-10 · Wizards of the Coast
  As each end step begins, if you haven't gained life that turn, Lathiel's triggered ability won't trigger at all. If it does trigger, you choose the targets and how the +1/+1 counters will be distributed as you put the ability on the stack. Each target must receive at least one +1/+1 counter.

Rulings: Scryfall · Wizards of the Coast