Now I've suggested this before in other grouped up suggestions, but it's a fair standalone one too.
Basis to it is that people who have bad ping can't react to taking damage as easily as players with good ping. The solution is to give players with bad ping more "mercy frames" so that they can react to damage more readily.
How I would implement it would be that for every 50 ping you have, you gain an additional 0.25 seconds of mercy frames. This number stacks up to a maximum of 500 ping, at which point mercy frames would not last any longer.
Here's a quick rundown:
- 0-49 ping - current mercy frames
- 50-99 ping - 0.25 more seconds of mercy frames
- 100-149 ping - 0.5 more seconds of mercy frames
- 150-199 ping - 0.75 more seconds of mercy frames
- 200-249 ping - 1 more second of mercy frames
- 450-499 ping - 2.25 more seconds of mercy frames
- 500+ ping - 2.5 more seconds of mercy frames
...
I would assume to take an average of the past 5-10 seconds to decipher which level of invinciframes to give the player. Alternatively, the ping of the player the moment they get hit would determine their invinciframes.
Someone playing lockdown could intercept their own packets to feign as much ping as possible, giving them the maximum amount of invinciframes always.