Here are a few of my own. I'll put in backstory if anyone wants it. Kysis, Prime Reaver: [spoiler]The fight takes place in a vast bunker below Titan. The architecture is Hive-like and the room is big with parts of it elevated and sprawling. Kysis spawns in the middle, performing a large AoE attack, and then goes to the centre stage. There are 9 red doors - 3 on the left, 3 on the right, 3 in the middle. There should be 2 players on each side. Stealth Reaver Vandals and Exploder Shanks spawn in large quantities from the doors. After a short time, 3 cloaked Stealth Servitors will spawn from a random door on each side. Only one will be able to be damaged - the side that has that Servitor must destroy it as quickly as possible, before "Servitor shockwave transmitting" appears and the team wipes. Killing that initial Stealth Servitor causes everyone on the team to gain a 10 sec buff called "Light Amplified" which lets the other 4 players quickly kill their Servitor. When this is done, Kysis will fire his gun a lot more and "Kysis summons the Enraged" pops up. 3 Enraged Servitors now spawn, as well as a TON of enemies. One person on each side must shoot the Servitor to get its attention, then lure it to the large plate at the back of the room. The other person must control the immense number of enemies. Once there, it will sacrifice. This causes a rune to light up. When all 3 are sacrificed, "The sacrifice is corrupted" appears and Kysis staggers. A blue circle lights up randomly on one of the sides. Inside it, you can damage Kysis. All teammates get a 15-second timer called "Accelerated Light". During this time, 5 people must DPS the boss, while another must hunt the Stealth Servitor that spawns randomly. At the end of the 15 seconds, Kysis will teleport to where you are and perform his AoE attack, so all players must be at the Servitor before then. The Servitor drops the next DPS circle where it dies and resets your buff, so the location of the circle is always changing randomly. Only 2 Servitors spawn, allowing for 45 seconds of time to damage the boss. Once all three buffs are expired, Kysis returns to the middle and the cycle resets again. Rinse and repeat to destroy Kysis, Prime Reaver. After one cycle he fires twice as fast, and after two cycles he summons Web Mines in random locations as well.[/spoiler] Challenge Mode: [spoiler]Every player must destroy a Stealth Servitor during the damage phase. This requires the entire team to be mobile and on the ball, as well as forcing the team to fight Kysis at full strength on the third cycle.[/spoiler] The Saracen [spoiler] The Saracen is an enormous Vex Cyclops, the size of Oryx, atop a dark machine within Nessus. The fight takes place on the surface of the planet at the machine's top, in a large sandy arena with Vex constructs jutting out everywhere. You trigger the fight by shooting The Saracen's eye rapidly. It will activate and shoot at you. Hobgoblins on posts around the arena spawn occasionally. There are also multiple mines in the arena that will Detain you if activated. For the duration of the fight, players have to shoot at The Saracen's eye to damage it significantly. However, staying in its sight for too long will give you the "Saracen's Fury" debuff which will quickly kill you unless you leave the boss's sight, and remains for 30 seconds. However, you can also stack the Fury debuff up to 3x by killing enemies. At 3x, you have the option to "Discharge Vex Energies" at the base of the Cyclops, dealing extra damage to The Saracen. At the rear end of The Saracen are 2 Confluxes. During the fight, Minotaurs and Goblins will spawn and try to sacrifice themselves to it. If one does, it will make The Saracen immune for a minute and enemies will flood the arena. Half the team should focus on DPSing the boss, then the other half should be at The Saracen's back keeping enemies off the Confluxes. People should switch around when they have the Saracen's Fury debuff to keep up DPS. This process keeps up for 90 seconds without The Saracen going immune. "Vex Constructs Active" appears and half the team is blinded with the "Voidmark" debuff. The other half of the team must run to The Saracen's base to get the "Cleansed Light" buff, but this slows you down to a crawl. The blinded and Cleansed must meet to restore everyone to normal and the fight resets. At half health, The Saracen spawns enemies at the other two quarters of the arena, and at 25%, it spawns Hydras at the Confluxes and fires much faster at the DPS team. Repeat until it dies - The Saracen will explode violently and the path downwards will open. [/spoiler] Challenge Mode: [spoiler]Whenever the Saracen's Fury debuff is acquired, it must be discharged at The Saracen's base after stacking to 3x. This can be avoided by simply switching the DPS group before the Fury is acquired, but you lose out on lots of DPS. The difficulty lies in killing the adds in time and surviving the trip to the base. [/spoiler] I'll add some more soon.