There is another series of Signs called "Bind", which has 3 different iterations, each with a number attached to them (1, 2, and 3). This can be used in a variety of ways, but the most common is for Black Mages to use "Sleep" on those targets, effectively taking them out of the fight for a little less than a minute in total (30 seconds, recast reduces to 15 (total 45), then recast reduces it to 7 (total 52) ). This can be EXTREMELY useful as it can greatly increase survivability, especially if there is a particularly annoying or high-damaging enemy that requires a lot of attention, but can't be dealt with right away. This also works on select bosses (such as the pirate captain in Sastasha), but only a small handful of them.