When Dr. Mundo's passive ability increases his might based on cards in the trash, does this happen before or after spell effects resolve? Specifically, does the spell card going to the trash save Mundo from lethal damage, and how does this interact with might modification effects like Convergent Mutation or Switcheroo?

Ruling: Cards go to the trash as part of the resolution of the card, which happens before cleanup. This means Mundo's passive will increase before checking if he dies from damage. When might modification effects like Convergent Mutation or Switcheroo are applied, they snapshot the might difference at the time they're played, then Mundo's passive increases by 1 after the spell resolves and goes to the trash.

Sequence:

• Spell effect applies (damage dealt or might modification snapshotted)
• Spell card goes to trash as part of resolution
• Mundo's passive recalculates with the new trash count
• Cleanup checks occur (such as whether Mundo dies)

Nuances:

• Convergent Mutation only increases might, it cannot decrease
• Might modifications from spells like Switcheroo snapshot the difference and apply it continuously for the turn
• If trash cards are recycled or removed after a snapshotted might modification, Mundo's passive adjusts but the snapshotted modification remains unchanged
• When multiple might modifications happen simultaneously, apply increases (+) first, then decreases (-)