If someone has two Zhonya's on the field and a unit dies, do both Zhonya's trigger and get sent to trash?

Ruling: No, only one Zhonya's is sent to trash. The first Zhonya's replaces the death with a recall and goes to trash, while the second Zhonya's stays on the board because there is no longer a death to replace.

Sequence:

• When a unit would die, both Zhonya's replacement effects are available
• You choose the order in which they apply
• The first Zhonya's replaces the death with a recall and is sent to trash
• The second Zhonya's has no death to replace, so its entire effect (including going to trash) does not apply
• The second Zhonya's remains on the board

Nuances:

• Zhonya's uses "would die" language, not "when it dies" - this means once the first replacement happens, the unit is no longer dying
• If multiple units die simultaneously, you can choose which units to save with each Zhonya's, saving up to two units before both Zhonya's are in the trash