Coin adding has to do with adding a coin to a combo after having already started the combo by shooting a different coin. For example, you throw a coin behind a Cerberus, shoot that coin through the Cerberus with your electric railcannon, and then quickly switch back to your pistol and throw another coin. The railcannon hits your original coin, and then reflects back and hit the second coin as you are throwing it. That would be a coin add.
If you haven't seen it before, I strongly strongly recommend watching HerbMessiah's video on coin mechanics, it's very good. If you aren't willing to watch the whole thing, 14:05 is the timestamp if you want to watch specifically the part on coin adding.
Its really fun is what it is, but the vid does explain every thing really well
- The top 3 session recording requirement has been removed.
- Now top 10 runs require Steam Overlay's in-game FPS counter to be enabled and visible in the recording, preferably with high contrast.
- If you have problems with the overlay disappearing, try running Steam as administrator.
- If using OB
