Pyramid Plunder advice:
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General notes:
Do not play this minigame if your Thieving is below level 71. It is a waste of your time. In fact I would not recommend it under level 81 -- if you want to level up to 81, the best method in my opinion is to pickpocket Knights in Ardougne. For a bit of distraction you might also try safe-cracking in the Rogue's Den.
NEVER USE LOCKPICKS. They reduce your experience and don't save you time. Don't have a lockpick in your inventory.
NEVER USE WATERSKINS. You don't need to worry about desert heat damage if you play the game correctly.
If you don't have a scepter, buy one on the market. You will find one eventually and can sell it for the same price you paid. The scepter makes things go much faster. MAKE SURE YOU BUY A FULLY CHARGED SCEPTER. The price difference is negligible and it's a pain to get to the pyramid without one.
There are 3 charges on the scepter. You should wield it and allocate two inventory spaces to antipoison, nine spaces to food items (sharks are best), and one space to coins. Wear a duelling ring or an amulet of glory as well, and light armor. Favor low weight over protection. The best armor here is probably full Rogue Armor if you have it. Well duh, it is a Thieving minigame
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Play through the pyramid THE FIRST TIME like this:
SCEPTER CHARGE 1: [from anywhere in RuneScape] Teleport to Jalsavrah (the minigame). Collect as many gold artifacts as you can but make sure extra spaces in your inventory are all stone artifacts. If your level is relatively low, just go with the more valuable artifacts as appropriate.
SCEPTER CHARGE 2: [from just outside the minigame] Teleport to Jalsavrah and play through again. Make sure by the end of this game that you have enough artifacts to recharge the scepter. The most cost-efficient way to do this is with 12 stone artifacts; the most experience-efficient way to do this is with gold artifacts and never to teleport to the Agility arena. The experience difference being negligible, I would recommend stone artifacts.
SCEPTER CHARGE 3: [from just outside the minigame] Teleport to Jalsavrah. Talk to the mummy and he will automatically offer to recharge the scepter for you. Accept and then enter, ready to play again. Collect as many valuable artifacts as you can.
Play through the pyramid AFTER THE FIRST TIME like this:
SCEPTER CHARGE 1: [from just outside the minigame] Teleport to Jalustrophos, the Agility pyramid. Sell everything to Simon Templeton (select the "Flog the lot" option).
SCEPTER CHARGE 2: [from Agility pyramid] Teleport to Jalsavrah and play through again.
SCEPTER CHARGE 3: [from just outside the minigame] Teleport to Jalsavrah, recharge, and play through again.
REPEAT FROM SCEPTER CHARGE ONE [from just outside the minigame].
Skeptics will note that this way you are selling items only one round after recharging your scepter, and that if you have multiple scepters you can allow yourself to accumulate more valuable items before selling. To that my response is simply that it takes so little time to sell items, you will actually make more money AND experience in the long run if you just run through and sell every two trips as per my suggestion. Further, you will conserve inventory space for additional food and antipoison items.
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While playing through the pyramid:
Loot the golden chest every time (or as of room 3 if you're high-leveled). Loot the coffin only in rooms 7 and 8.
Loot about half of the urns in the second-to-last room you can enter, with single clicks. Loot all of the urns in the last room, and if your level is only a few higher than the entrance requirement, loot them by FIRST right-clicking to "check" for snakes, and then left clicking after the snake appears. You will get the same amount of experience and it's much faster.
If you become skillful at the above, you can loot more and more of the urns in the second-to-last room until you become good enough to get all of them. Whether or not you get lucky with finding doors in earlier rooms can sometimes play into this as well.
When playing through rooms, always get urns first, then golden chest, then the coffin LAST. If you are in the second-to-last room you can enter and release scarabs from the golden chest, LEAVE THE ROOM without trying to open the coffin. Obviously if you are in a low-level room and are not interested in urns, then get the chest quickly by clicking on it and then promptly leave. Here is an example of a walkthrough for a level-82 player (can enter up to room 7):
Room 1: Find door to room 2.
Room 2: Find door to room 3.
Room 3: Get golden chest. Find door to room 4.
Room 4: Get golden chest. Find door to room 5.
Room 5: Get golden chest. Find door to room 6.
Room 6: Open about 50% of the urns with left click. Get golden chest. If no scarabs, open coffin, otherwise skip. Find door to room 7.
Room 7: Open all urns with right and then left click. Get golden chest. Get coffin even with scarabs (pray to avoid damage). If you have time left after all is looted, go through the exit door.
If you are about to run out of time in two seconds, then no matter what room you are in, make sure you click on the golden chest, and if you still have one extra second, try to click on the coffin. Even though it takes a few seconds to open the coffin, sometimes if you click it just before your time expires, you will still get the prize.
NEVER TRY TO KILL MONSTERS. It is a complete waste of your time and worth very little experience. If you unleash a beastie, switch your protect-from-melee prayer on and find the door to the next room. You can recharge your prayer just outside of the minigame to the southwest.
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Final additional notes:
Play the minigame without friends and in an isolated world. Unfortunately, having other people around sometimes makes a door you already checked and found dead-ended suddenly turn into the door you need ... and this can cost you a lot of time and thus experience.
Keep your hitpoints very high -- once you start taking damage, eat food. Don't waste food, but eat it as soon as you can, since inventory space is at a premium. Also, once you are completely out of food you should have high hitpoints so you can play through once or twice more before teleporting to the bank via your Duelling Ring / Amulet of Glory for restocking.
Handle restocking logically: don't teleport to the bank to restock except RIGHT AFTER SELLING to Simon Templeton. Time your trips accordingly. Otherwise you will find yourself dropping artifacts needlessly that you could have sold.
When you are ready to quit for the day, do so intelligently: don't log out while INSIDE the pyramid, or you will be back outside when you log in again. If you are ready to quit, wait until you've completed a round and then log out BEFORE you use your teleport. That way, you will be able to start your next trip with a teleport and won't have wasted one in the process.
Don't worry about having a full inventory when you open the golden chest or coffin. If the item is a nice golden one, it will appear at your feet and you can drop/pick up accordingly. IF YOU FIND A SCEPTER WITH A FULL INVENTORY, YOU WILL STILL GET IT, because the mummy will boot you from the pyramid and the scepter will be at your feet outside. Trust me, I found 4 scepters in my time, and two of them when my inventory was full.
Credit to Sir Valimont for this miniguide