Ares is a free and open source client that can be found on Github. The github page has been set up very nicely. There is a decent amount of information on the client, and there are instructions on building the client for yourself.
Interesting Hacks Offered By The Ares Client:
[1] – Anchor Aura This module automatically places and explodes Respawn anchors to kill opposing players, it obviously only works in the overworld.
[2] – Crystal Aura This module automatically places and explodes End crystals to kill opposing players, the module itself is slightly customizable with a few different settings and modes.
[3] – Kill Aura This module automatically attacks enemy players or mobs. Unfortunately this module does not have as many settings as other clients I have reviewed.
[4] – Firework Aura I have never seen this module before, The module itself attempts to trap an opposing player. It will then spam fireworks dealing damage to them.
[5] – Bed Aura This module automatically places and then right clicks beds in the nether and end dimensions, to blow up your enemies.
[6] – Offhand This module lets you hold an item in your offhand, but then it automatically switches to a totem when you reach a certain health level.
[7] – offhand gap When enabled this module will automatically gappel on a right click, even if you are not on your grapple slot.
[8] – Surround This module automatically surrounds your feet with Obsidian to prevent other players from blowing you up with end crystals or beds.
[9] – Auto City This module automatically breaks the blocks surrounding an opposing player’s feet, so that you can deal more damage.
