Order of Sacred Dusk

• WOTC Official Reminder Textofficial rules
  Lifelink — Damage dealt by this creature also causes you to gain that much life.
• WOTC Official Reminder Textofficial rules
  Convoke — Your creatures can help cast this spell. Each creature you tap while casting this spell pays for or one mana of that creature's color.

• WWizards of the Coast2023-11-10
  Official Ruling
  A creature attacks alone if it's the only creature declared as an attacker during the declare attackers step (including creatures controlled by your teammates, if applicable). For example, exalted won't trigger if you attack with multiple creatures and all but one of them are removed from combat.
• WWizards of the Coast2024-01-12
  Official Ruling
  Tapping an untapped creature that's attacking or blocking to convoke a spell won't cause that creature to stop attacking or blocking.
• WWizards of the Coast2024-01-12
  Official Ruling
  Tapping a multicolored creature using convoke will pay for or one mana of your choice of any of that creature's colors.
• WWizards of the Coast2024-01-12
  Official Ruling
  Because convoke isn't an alternative cost, it can be used in conjunction with alternative costs.
• WWizards of the Coast2024-01-12
  Official Ruling
  You can tap any untapped creature you control to convoke a spell, even one you haven't controlled continuously since the beginning of your most recent turn.
• WWizards of the Coast2024-01-12
  Official Ruling
  If a creature you control has a mana ability with in the cost, activating that ability while casting a spell with convoke will result in the creature being tapped before you pay the spell's costs. You won't be able to tap it again for convoke. Similarly, if you sacrifice a creature to activate a mana ability while casting a spell with convoke, that creature won't be on the battlefield when you pay the spell's costs, so you won't be able to tap it for convoke.
• WWizards of the Coast2024-01-12
  Official Ruling
  When calculating a spell's total cost, include any alternative costs, additional costs, or anything else that increases or reduces the cost to cast the spell. Convoke applies after the total cost is calculated. Convoke doesn't change a spell's mana cost or mana value.

Rulings via Scryfall