Well I did some testing on this, and I got these results Encore gives back some energy with each kill Mask of the third man reduces energy used when pressing melee button (not sure which energy part) Now, how energy is used When you do a normal arcblade attack, some energy us used up just for the action and some more energy gets used if you actually make contact with an enemy. Mask of the third man, from what I see, does not affect secondary arcblade abilities, while encore can. (if you kill multiple enemies with one of the 2 arcblade damaging abilities, you can replenish more energy than you use up.) (edit: Hungering blade btw, heals you, it does not replenish energy, Encore, replenishes energy)