When Switcheroo swaps the might of Dr. Mundo (who has high might from his graveyard passive) with a low might unit, does Mundo's passive continue to apply after the swap?

Ruling: When Switcheroo swaps might values, it applies in the arithmetic layer as a might decrease/increase. Mundo's passive continues to be calculated simultaneously with the Switcheroo effect, so after the swap Mundo will have his new base might plus his graveyard bonus.

Sequence:

• Before Switcheroo: Mundo has base might + graveyard bonus (e.g., 6 + 14 = 20 might)
• Switcheroo resolves: Creates a might decrease to bring Mundo to the swapped value (e.g., -19 might modifier)
• Mundo's passive continues applying: Base + graveyard bonus + Switcheroo modifier (e.g., 6 + 14 - 19 = 1 might)
• If graveyard changes: Mundo's might adjusts accordingly (e.g., adding one card makes him 2 might)

Nuances:

• The exact mechanical implementation of "swap" is not yet fully defined in the rulebook
• The effect is believed to work in the arithmetic layer rather than trait altering layer, though this awaits official confirmation
• Mundo's passive is not "current might + graveyard"; rather his current might already includes the graveyard calculation