Sliske's Endgame/Quick guide

Invitations

 * Speak to Relomia in Draynor Village
 * Speak to each of the gods
 * Speak to Seren and Zaros up the stairs NE of the Prifddinas lodestone
 * Speak to Saradomin on the of White Knights' Castle
 * Speak to Armadyl on his tower near the Clan Camp
 * Speak to Zamorak on the of Black Knights' Fortress
 * Speak to Icthlarin in Death's office
 * Return to Relomia
 * Speak to Relomia in Heart of Gielinor campsite (west of the entrance). Pick a side or not.
 * Defeat Nomad (he uses melee/mage and doesn't use special attacks like in Nomad's Elegy)

Maze

 * Solve the maze. Goal is to reach the exit at the far north-east. The solutions to both mazes are found below.
 * Next, navigate the maze and pass through the door 4th from left of the map. (On your minimap, you will see 4 openings in one section. Choose the 4th opening, as the 1st and 2nd will lead you to the 3rd door and vice versa, so if you keep going in circles means you are at the wrong track.) Follow the path down to the closest large room and a cutscene will play with all the other gods.
 * Head back down the long path to the next room with a big floating rock in the middle, a solution panel, and a shadow caster in each corner of the room. You will have to cast a certain face depending on what the faces say on the solution panel. NOTE: This will be different for everyone. There are SIX different shadow caster puzzles!
 * Tip: maximize your minimap, where you are after completing a puzzle, imagine the routes you take before running to save time. If two roads split, choose one first, then remember the next. It is often both road intersects (logically, they want you to solve the maze). If all roads lead to a certain point, that's where you want to head (mostly).



Fight
The final fight takes place in several segments. The first consists of fighting against wights of increasing difficulty, kill enough of them to increase the progress bar on top. The next stage is fighting with the assistance of the barrows brothers against Gregorvic, Nomad and Linza. It is recommended to kill Nomad first, and then deal with Linza. The spirits that Gregorvic spawns will heal him when they reach him. It is enough to tag them so that they attack you.

The third stage is the fight with Sliske himself. Once he reaches around 10,000 health he will teleport back up atop his rock, there are several things you can do to stop him; attack the power source in the middle of the arena, jump up on the rock below him and throw him down, or teleport into one of the nearby portals. All three must be done in no particular order. Upon the third time, you will enter the shadow realm again with World Guardian powers. All cooldown times are halved, and you're permanently at 100% adrenaline. Kill Sliske. This will trigger a brief cutscene depicting a fight between the World Guardian and Sliske. It will end with the World Guardian stabbing Sliske with the Staff of Armadyl. Once the cutscene ends, you will be teleported to Jas, where you will have a brief discussion. She will tell you that you must prove that life deserves to exist. You're then teleported back to the Heart. A brief discussion with Armadyl, Icthlarin, and Death ensues. Icthlarin tells you to head to Relomia in Draynor and tell her of the death of Sliske. Quest complete!