From the brewery:

Collaboration with Moksa with vanilla from literally everywhere. A blend of long boil imperial stout aged in rye barrels 24 months + bourbon barrels 40 months. Conditioned on the most obscene amount of:

• Vanuatu Volcanic Vanilla beans 
• Ugandan Planifolia Vanilla beans
• Tahitian Tahaa Vanilla beans
• Comoros King Size Vanilla beans
• Papua New Guinea Morobe Province Vanilla beans
• Madagascan Pompona Vanilla beans
• Madagascan Black Planifolia Vanilla beans

All the vanilla.