Do replacement effects that save units (like Unlicensed Armory's power payment, Zhonya's save, or Sett Legend's save) open a chain that can be reacted to?

Ruling: Replacement effects indicated by the word "instead" (like Zhonya's, Sett Legend, and Unlicensed Armory's save effects) do not use the chain and cannot be reacted to. They replace one action with another without opening a reaction window.

Sequence:

• Unlicensed Armory can be reacted to when initially played (during the exhaust and discard)
• Once the unit gains the protection, the replacement effect itself (paying 1 power to save) does not open a new chain
• The replacement effect simply replaces dying with recall when it would apply

Nuances:

• Some replacement effects are optional, allowing the controller to choose whether to apply them and pay any indicated cost at the time they would apply
• To disrupt the protection, you must respond to Unlicensed Armory when it's played (e.g., removing the targeted unit before it gains protection) or use a later chain-starting non-replacement effect