Rule 821.1.b
Weaponmaster is a Play Effect that chooses an Equipment you control and allows you to pay its Equip cost at a discount, regardless of the usual timing of the Equip ability, to Attach that Equipment to the unit with Weaponmaster.
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Weaponmaster is a Play Effect that chooses an Equipment you control and allows you to pay its Equip cost at a discount, regardless of the usual timing of the Equip ability, to Attach that Equipment to the unit with Weaponmaster.