Someone told me they already reported this, but unless it was a security ticket I don't believe they did, so my bad if I'm just missing it.
Bug- Using the moves Absorb, Mega Drain, and Giga Drain when confused and you "damage yourself while in confusion" give free health to the user.
How to replicate- Enter in battle with a confused pokemon. Use one of the listed moves until you get the "*user* hurt itself in confusion!" and the pokemon who is supposed to hurt itself instead will gain health.
Additional note- Honestly I am not sure what other moves there are that drain opposing health and give the user health, but those may be broken as well.