User blog comment:B214/Volume 23 discussion blog/@comment-26293136-20170612235918/@comment-29963364-20170613004705

[Twice Critical] doubles the user's power only once.

Siegfried's [Twice Critical] is the same. His Balance Breaker, [Caos Edge Asura Ravage], creates four Dragon Arms from his back. Each arm doubles his power once.

Here's the formula:

1 x 2^4 = 16

So his power is multiplied by 16.