Gronnowl+During combat, unit's Atk/Spd/Def/Res boosted by number of adjacent allies x 2.
These weapons have a unique and interesting effect, and are one of only a handful of ways to apply buffs to oneself. For each ally standing adjacent to the user (maximum of three) the unit receives an increase of two to all stats while in combat. These buffs are invisible, similar to those granted by Spur skills, and do not boost damage of Blade tomes. These weapons are by nature, difficult to predict, especially as their use and damage can be largely incidental, even if the player or AI is not trying to make use of it.
The effects of these weapons can be used to full effect, so long as the player uses a complete team of four and positions them around the correct unit. However, as the buffs are invisible, they can be boosted further through allies with Spur skills of their own, or tangible buffs such as those from Hone/Fortify skills. These weapons work the best when the user is buffed into the stratosphere, but this requires a significant amount of team support. Ally supports stack well with Owl Tomes, allowing a user to get a significant stat boost with just one person. Dual Spur skills also provide the same benefit.
These weapons have two weaknesses. Firstly, the non-legendary forms suffer from a hefty power reduction (tome variants have only 10 might). Secondly and most importantly, it can be very difficult and sometimes impossible to make use of their effects due to map layouts. Many arena maps feature long bridges or other structures that prevent the required positioning. Arena in general often requires careful and specific positioning to win, luring and repositioning your units. This makes it hard to take advantage of their power.