The way things are supposed to be done.
Firefly is one of the most advanced anticheats ever created, it utilizes an intelligent alert system and features high customizable level while maintaining simplicity. The anticheat can detect 99% of all combat, movement, connection and world cheats while also preventing cheats from even being used. The anticheat does not require protocollib and is extremely light-weight while still being able to detect most of the cheats.
Price: 200$, Source: NFS
Firefly Anticheat (Lite)
A light version of firefly that only blocks and detects essential cheats. This includes most of the combat and movement detections, however, ghost client detection is not included, which means it does not have checks for detecting aim, autoclicker, wtap and other cheats that are usually used by closet cheaters. This anticheat is designed for preventing people from blatantly cheating around your server.
Price: 25$/month, Source: NFS
FireflyAI (Coming soon)
A combination of Machine learning and AI. This version of firefly is a complicated and advanced detection system that analyzes player behavior for cheat detection, which means even if a ghost client manages to fully emulate a real player would be still picked up by the anticheat, however, it is extremely performance intensive and requires a GPU server and huge amount of storage, hence the high price tag.
Price: 100$/month, Source: NFS
HyperProxy (Coming soon)
HyperProxy is a massive filtering cluster. It proxies minecraft traffic first before it reaches your server and defending it against DDoS attacks, it also decreases latency due to the fact it runs through a proxy network which means the traffic runs through dedicated 10gbps network lanes. It's also easy to setup and can be done with basic ssh knowledge.
Price: 0.004$/1TB or ((0.25$ - 1$)/player)/month
This is a fork of iHCF, however, it has all of the bugs fixed and contains major performance upgrades. By buying this plugin you also gain access to nSpigot Enterprise.
Price: NFS, Source: 100$
nSpigot 2.0 Enterprise
nSpigot enterprise edition is a multithreaded high-performance 1.8.9 spigot which has been backported to 1.7.10 which can fully utilize up to 8 cpu cores/threads and can hold 1000+ players. It also has a lot of knockback modification values including values for bow and rod kb. It also features anticrash and antiphase. The main feature of the spigot is it's over-all tick processing, it has smart speculative ticking which skips things that do not need to be processed which gives it a huge performance boost. This spigot supports 1.7-1.12
Price: 100$, Source: 200$
nSpigot 3.0 Enterprise
nSpigot enterprise edition is a multithreaded high-performance 1.8.9 spigot which has been backported to 1.7.10 which can fully utilize up to 8 cpu cores/threads and can hold 1000+ players. It also has a lot of knockback modification values including values for bow and rod kb. It also features anticrash and antiphase. The main feature of the spigot is it's over-all tick processing. This spigot does not have a "tick-loop" which makes it the first one of it's kind, plus it has fully asynchronous worlds which is extremely useful for plugins like StrikePractice or any other plugins that support multi-world arena systems since it essentially makes it able to handle unlimited amount of players. This spigot supports 1.7-1.12
Price: 150$, Source: 300$