Be careful in the Chaos Tunnels, as the many of the monsters may be aggressive. You may find it useful to turn off auto-retaliate in the tunnels.
For average players, 3 prayer potions and a full inventory of monkfish should be more than enough for the whole miniquest.
Due to the occasional random nature of the chaos teleports, equipping an anti-dragon shield until you get to Bork is a safe decision. Bronze dragons are in two caverns, and you must go through one of the caverns. You may also be teleported to one of the areas with poison spiders, so bringing an Antipoison is also helpful if your combat level is 128 or lower.
Do not underestimate the Dagannoths, as many high-level players have been caught by surprise by the rapid 200s that they hit. If your life points are not above 700, they will most likely be able to kill you in a matter of seconds. Put on Protect from Missiles to be safe.
Get past the Shadow spiders as quick as possible to conserve prayer if you are level 104 combat or lower. If you use the path shown below, you would not need to enter their room.
Do not attack the dust devils: They are non-aggressive but deadly if you are not wearing the proper equipment.
Some caverns may be safe to you. For example, Moss Giants are not aggressive to higher levels (90+). Use these safe caverns to recuperate run energy and life points, eat, potion up, and equip.
It may be possible to make the next cavern non-aggressive by standing close enough to it for a while.
You may experience random portal failure and be teleported to a random destination.
The room with Zamorak warriors, rangers and mages is by far the most dangerous. Knowing this, a player should heal up in the fire giants room, and make sure you are facing North. Run straight to the South side of the room, using Protect from missiles in the first half and Protect from melee in the second half.
Use the map above to make your way through the tunnels and follow Surok.
Note: You will find many enemies in the tunnels. Most attack with Melee, so Protect from Melee will prevent your taking a lot of damage. However, the Chaos Tunnels are long and if your combat level is below 105, shadow spiders may drain your Prayer. If you intend to use Protect from Melee, you may want to bring a prayer potion or two.
You encounter Surok three times in short cutscenes in the tunnels, based on the route you take:
In the first encounter, in the deadly red spider room, you see him kill two fire giants in one hit (6700 life points each).
In the second encounter, in the skeleton's room, you attempt to stop Surok, but he summons two big wolves—not to mention the undead already in the dungeon—to attack you. Do as you wish with them, but you can simply run past them to the next portal.
The last encounter is near the Dagannoth room (which is in the most north-west region of the Chaos Tunnels). In the Dagannoth chamber, look to the west for a portal with the familiar footsteps. Enter it, and you find Surok for the final combat. Using Protect from Ranged is recommended.
Note: From here on, after you have reached Bork, you may use the map to the right to reach Bork from Edgeville. You can restock everything you need for the battle and take the route from Edgeville. Only use this route after you have reached Bork. Otherwise, it will not work.
You see a cutscene, where Surok summons Bork (level 107), who fights exclusively with melee. He has fairly high defence, but is weak to crush attacks. He is immune to stuns as well as poison and deflect damage, and his melee attacks can hit well into the 2000s.
Turn on Protect from Melee or Soul Split, and attack him. If you are using range or mage, you can run from the west wall to the north wall, which will get him caught in a safe spot until he summons his minions. Ranged is not recommended, however, as he is extremely resistent to ranged attacks. Magic works well, though.
He can be defeated fairly quickly using Bandos armour or barrows armour and a Saradomin sword or better. A godsword can also be used, but at a slight cost of accuracy due to being a slash weapon and not a crush weapon. The abyssal whip can also be used with a suitable off-hand to provide a moderate rate of success.
Due to Bork's immunity to deflect damage, the Deflect Melee ancient curse will not reflect damage back to him, and therefore has no extra benefits from the normal protect from melee prayer. When Bork is at 3/4 health, he will summon two to four Ork legions (level 70) to attack you. If you stand near them, they will attack you with melee. Otherwise, they will attack you with Ranged. However, they will stop attacking you if you run across the cave. It is recommended to stand near them, if you are using the Protect from Melee prayer.
You can start the battle, leave, and restart it at a later time. This may be helpful if your resources have dwindled while travelling throughout the caves. It may be wise to begin the battle, teleport out, and reenter when you are fully stocked using the shortest route to the final battle.
If you intend to tank Bork's attacks and pray against Surok's magic attacks, it is highly recommended to bring a summoningfamiliar, because he tends to attack your familiars quite commonly.
Warning: Surok attacks you every 20 or so seconds during the battle, with magic that can hit into the 500s-600s. He cannot be attacked, however, as a magical force will stop you from doing so.
When you defeat Bork, he falls to the ground. Surok, realising that he is defeated again, then calls Zamorak for help and teleports out of the cave.
Quickly, grab the monster's drops and get out, for the cave will be collapsing. You will lose some life points if you stay in the cave too long. (You will be damaged twice before being forced out of the area with your character saying "I'm getting out of here!")
Borked is Internet-technical slang for something that is broken, as in "that update borked" or "you totally borked the time rotor." In this case, the portals in the Chaos Tunnels are borked. This derives from political slang, originating with a judge who was nominated for the US Supreme Court in 1987, Robert Bork. The opposition party rejected his nomination, in what was a rare occurrence up to that point. Consequently, his name became a synonym for when any nominee for a political post was not confirmed. The 2002 Oxford English dictionary defines bork as US political slang meaning "To defame or vilify (a person) systematically, esp. in the mass media, usually with the aim of preventing his or her appointment to public office; to obstruct or thwart (a person) in this way."
Bork is reference to the Borg, a race in the Star Trek universe who seek to forcefully add other species into their collective. The Ork Legions that Bork summons may shout phrases such as "We are the collective!" and "Resistance is futile!" which are references to the Borg in Star Trek.
Bork is also a portmanteau of the two words Big and Ork. This is played on in his examine text, which says "That's one Big ork."
"The Hunt for Surok" is a pun on the Star Trek movie The Search for Spock. Surok is also similar to the name of Surak, who was the Vulcan who instituted the philosophy of logic over emotion, which caused the split of the Romulans from Vulcan.
Interestingly, Members who have completed What Lies Below can start the miniquest on free-to-play servers. They can encounter Surok near the entrance, and see the cutscene where he enters the tunnels. However, they cannot enter the tunnel itself, thereby preventing the miniquest from progressing further.
The RuneScape news article about this miniquest contained the line "for there are worse things than simple orks in the dark places of this world." This is from The Lord of the Rings: The Fellowship of the Ring when the characters go into the Mines of Moria.