Player A has the amulet and chooses to fight Player B. Player B casts a summon spell (someone Phoenix or the like) to fight this battle so he doesn't get rofflestomped and lose his warhorse.

Is this legal?

The summon spells specifically use the word YOUR as in not targeting the amulet-wearer. After a long discussion and seeing that only similar tangents to this had been covered by previous rules questions we decided to go with it anyways, but I would like clarification just incase this happens again. This gives spellcasters another way to avoid confrontation against amulet wearers in the future.

Thanks and happy new year to everyone!

-pfx

Amulet protects the bearer from spells that target him, not from consequences of spells cast on other targets.

The Summon Phoenix move was perfectly legal and the same goes for all Spells that protect or boost another character, such as Psyonic Blast.