Soul offering spike disappears on weapon swap, but the buff remains.

Soul offering on weapon set 1 and 2, minions on weapon set 1 ONLY.

When swapping, the spike is removed as if it was the minion that was sacrificed, however, the buff granted by the spike remains. The icon remains, and the damage on the skills screen is still buffed.

This can be used to bypass the condition of "If the spike dies, the buff disappears immediately", as the spike is not on the field and thus can't be killed.

screenshot of the buff icon without the spike: