I got DDoSed / flooded during games?

Check this - https://youtu.be/I2x5vOnSyx4 , P/L skyrockets somewhere at 03:00 when I'm close to winning
Look how bad my packet loss became closer to end. Same also happened in next 3 games, although there it was starting earlier (when I was like 15 frags) so I couldn't win anymore, every time that '[BOT]GATTS' won while me having almost 100 packet loss and even chat not working anymore.
What I noticed:
1) if I tried to join any other server it went well and I had no lag
2) if I tried to join this same server then nothing happened for 40-50 seconds (was just sitting in server browser), and then it joined
3) I could ping anything besides xonotic, open websites etc, everything was normal, no packet loss
4) I don't use wifi of any kind
5) after these 4 games I immediately enabled my VPN (which has DDoS protection) and lag problem was immediately solved, never saw any P/L at all for like 5-6 games (then I went off).
This never happened before so idk, it's just very suspicious.

That was one of Eris DM servers btw.

How can it be?
Also it's a bit weird DDoS if only connection between me and this particular server got spammed. Is it technically possible for some player to overwhelm other player with some packets and stuff (maybe via modded client)? But then it's also weird than VPN solved the whole problem completely (albeit adding a bit to ping but that's expected).
You can also see this 'GATTS' also gets some packet loss but not nearly as much as me, could this be because he initiated flood somehow on his side?

I can upload other games with same situation too if you need, it's basically same - as soon as I start winning or getting close to overtaking this 'GATTS' my packet loss skyrocketed to almost 100 and everything frozen and became slide show. And one time I disconnected, returned to main menu but couldn't open server browser (just nothing happened when I clicked it) so I had to restart xonotic.

Check this - https://youtu.be/I2x5vOnSyx4 , P/L skyrockets somewhere at 03:00 when I'm close to winning
Look how bad my packet loss became closer to end. Same also happened in next 3 games, although there it was starting earlier (when I was like 15 frags) so I couldn't win anymore, every time that '[BOT]GATTS' won while me having almost 100 packet loss and even chat not working anymore.
What I noticed:
1) if I tried to join any other server it went well and I had no lag
2) if I tried to join this same server then nothing happened for 40-50 seconds (was just sitting in server browser), and then it joined
3) I could ping anything besides xonotic, open websites etc, everything was normal, no packet loss
4) I don't use wifi of any kind
5) after these 4 games I immediately enabled my VPN (which has DDoS protection) and lag problem was immediately solved, never saw any P/L at all for like 5-6 games (then I went off).
This never happened before so idk, it's just very suspicious.

That was one of Eris DM servers btw.

How can it be?
Also it's a bit weird DDoS if only connection between me and this particular server got spammed. Is it technically possible for some player to overwhelm other player with some packets and stuff (maybe via modded client)? But then it's also weird than VPN solved the whole problem completely (albeit adding a bit to ping but that's expected).
You can also see this 'GATTS' also gets some packet loss but not nearly as much as me, could this be because he initiated flood somehow on his side?

I can upload other games with same situation too if you need, it's basically same - as soon as I start winning or getting close to overtaking this 'GATTS' my packet loss skyrocketed to almost 100 and everything frozen and became slide show. And one time I disconnected, returned to main menu but couldn't open server browser (just nothing happened when I clicked it) so I had to restart xonotic.

Yes, looks suspicious. Wonder if it is possible to find a proper host who provides DDoS protection, maybe even Cloudflare could provide a shield which works? https://www.cloudflare.com/ddos/

I will need to look into this, because I have not really taken the time to understand how they attack, or how it works, but I have seen it before just as you describe. I will investigate.

Also, I have just setup a server at Hetzner, they also provide some protection of the server: https://www.hetzner.com/unternehmen/ddos-schutz

But again, need to dive into this, in order to understand the complete picture.

I've played with GATTS before and I would be very surprised if this would be something he would do in an attempt to win a public match.

i had this happen before. it was called DSL. shit internet happens sometimes out of nowhere