Carbon
This is probably the best spigot that I have ever used. The amount of KB types is insane. I was even able to make a near 1:1 replica of MMC KB. Performance is also great! I have not lost a single TPS using it on my Bedwars and Practice servers. I would highly recommend.
CarbonSpigot best Spigot
Great core, lots of optimization, and most importantly it's a pvp system.
Excellent Spigot! has lot of combat features. great performance for +500 players.
great core! has lot of futures like bow boost knockback settings - overall knockback settings - good configuration system and performance - best at anything it could handle the 400+ amount of players with a good performance
Very good spigot not the easiest to setup but with the right configs can make your server smooth just make sure you config it properly :D
Best Spigot and Good Support
this spigot is better then bukkit
Best 1.8.8 Spigot for PvP Servers
Simply one of the best spigot forks for 1.8 out there.

I like how there are different types of knockback profiles. People that do not know much about knockback can easily configure one of the less detailed profiles while people who do know a lot about knockback have the option to customise it exactly they want it. With the "detailed" knockback profile I was able to create knockback which is close to MMC's sumo and boxing knockback.

I have heard from others that the performance is great. My server did not have that many players so I cannot really comment on this.

Finally, I'd like to mention that not every release was always stable. I had been using an older version (2.3.6) for a while because of this fact, but the developers of this product are very active and push fixes as fast as possible.

Carbon 4 seems to be working fine and I recommend anyone who is looking for a good pvp core to buy this product.
tbh I love this cause the optimization thing.
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