The Rite of Luna's Spear causes an Attack Moon Bridge to pierce the barrier of the caern totem and connect to the target caern. It must be enacted with the aid of a caern totem.
The ritualist rolls Wits + Enigmas. The difficulty of the roll is dependent on the level of the targeted caern: six for Level One or Two, seven for Level Three, eight for Level Four, or nine for Level Five. The ritualist may determine where the moon bridge opens in the caern if she rolls a number of successes equal to the level of the caern. A number of Gnosis points equal to the level of the targeted caern must be expended by the ritualist (or a total from all the participants in the rite).
Note that the use of this rite can be considered treasonous to the Garou, and Gaia's Vengeful Teeth will await any who teach it to the foes of the Garou. This rite may only be enacted on the Full Moon.
Source: Caerns: Places of Power