Best Zofia moment ever with my Team. (Happened in ESL)

Yep, that was added back in 2016:

Even though we’ve seen some great plays with it, most of the time Doc’s stim pistol felt too situational. We want to give Doc a gadget that makes him more useful, in more varied contexts. Giving his darts the ability to heal teammates means he can have a much more versatile role in more strategic situations. In the same way that Doc can revive himself from DBNO, Doc will also be able to self-heal as well.

Furthermore, he can now over-heal. Shooting a dart at a fully healed teammate or himself will provide a boost up to a max of 120 total health points for a limited time. The heal is 40 HP per dart, so even partially injured teammates can be over-healed. This over-heal is only temporary and will decrease 1 health point every 2 seconds back to 100 health points. We believe that this change will be a clear upgrade to his versatility and will make him a more interesting pick for the defense.

Source.

/r/Rainbow6 Thread Parent Link - v.redd.it