Dungeon of Doom

Here is a starter dungeon you can run for 5e using the basic rules. It assumes 4-6 level 1 characters.

1sq. = 10'

The Tomb of Oremor

Oremor was an ancient Orichalcan Dragonlord and architect of the strange structures men call dungeons.  He used magical means to shamble between dimensions. On the Forbidden Planet he learned to harness the power of the Id before returning to Ghenvek IV to bring Doom to its inhabitants. But that was long years ago. Now his body lays in a tomb in Hex XXXX, where it is served by a small priesthood that commutes from the City State of the Invincible Overlord.

General Features of the Tomb

• Ceilings are 15 feet high. Walls are made of dark granite. Doors are stone and require a DC 15 Strength (Athletics) check to open.
• Anyone who perishes within the tomb becomes a zombie within 24 hours - forever bound to serve Oremor in death.
• Random have a 1 in 6 chance of occurring every hour the PCs are in the dungeon.  If an encounter is indicated it is always an Acolyte and 1d4 Zombies. These encounters always have individual treasure equal to their number.

1. Entry Chamber

• A shaft from the surface shows light onto the water feature in this room - a small pool only about 3 inches deep.
• The pool has a small pipe in it that funnels water into a section of stone in the northwestern-most column.  This section of column, if rotated, will open the secret door to area 5. The secret door only stays open for 2 combat rounds before the mechanism automatically resets.  It can be stopped by a DC 20 Strength (Athletics) check, but a new check must be made each round it is being forced open.
• If the door is opened, it will attract a random encounter from the direction of area 3.  The acolyte will wait to attack until it thinks the party is divided on both sides of the door.
• A single, mutilated corpse of an adventurer in leather armor lies north of the pool, their blood mingling with it slightly. If anyone moves near the pool the corpse will animate as a Zombie.

2. The Holy Armor

• The room is dominated by a staircase that leads to a raised platform on which sits a set of plate mail - obviously set up in a place of reverence.  
• Candles line the side of the staircase, and obvious blood smears are apparent.
• On either side of the staircase are piles of gore - dead adventures with too little material left to animate.
• If touched, the armor rises and reveals it is an Animated Armor. If "slain" the armor functions as normal plate.

3. The Chamber of Secrets

• This room has strange, plastic wiring running in and out of the walls.
• The room-within a room has a glass panel on the wall with the secret door icon.  If touched, the section of wall with the panel will rise up, spilling out the monstrous contents of area 4.
• It will also open the door to area 6.
• The door to area 6 will not open without interacting with the panel. It could be forced open with a DC 25 Strength (Athletics) check.

4. The Monster Closet

• This room contains 4 Zombies who will shamble out to attack if the panel in area 3 is activated.
• The walls inside have a strange, bluish circuitry like pattern.

5. The Foul Pool

• This room is lit by a sickly grass that glows a dull green even in the cthonic chamber.
• The pool in the center is filled with acid (1d6 acid damage each turn submerged, no save). It is 20 feet deep.
• At the bottom of the pool is a leaden case that contains a Ring of Lightning Resistance and a large opal worth 150gp. 
• The secret door to the passage between area 6 and 8 cannot be opened from this side, but is obvious from within the passage.

6. The Zig Zag Path

• This room has an illusory floor, with only the clear tiles being able to be crossed.  
• Stepping onto the other tiles will drop the character 10 feet into a five foot deep pool of acid identical to the acid in area 5.
• The priest in area 7 can view the room through the adjoining sections and will use his Wand of Magic Missiles to attack those trying to cross.
• The secret door can be identified from the much lighter color of the granite - DC 10 Intelligence (Investigation) - but is only visible from down in the acid pool.  It swings on a hinge but moving it with the pressure of the acid means it takes a DC 10 Strength (Athletics) to open.
• The secret passage in the hallway to area 8 (leading to area 5) can be noticed by its lighter color, much like the secret door above, and can be opened more easily.

7. The Priest's Chamber

• The Priest here is the only permanent resident of the dungeon (other than the zombies) - with the acolytes returning cycling back to the City State.
• He has a small pallet, a Wand of Magic Missiles, and 2 Potions of Healing.
• His robes, if capable of being recovered, would be worth 50gp, and the cult is obscure enough that none would know its origin.

8. Guard Chamber

• An Acolyte And 3 Zombies guard the final resting place of Oremor.
• They hide behind the columns if they hear fighting in area 7. Once characters have actually entered the zombies will move to pin them in melee and the Acolyte will try to flank them and cast spells.
• The door to area 9 is polished bronze carved into a strange circuitry pattern, but requires the same open doors test as the others in the dungeon.

9. The Tomb

• The room is covered in polished bronze with the same pattern as the door, with a large leaden sarcophagus inside.
• The sarcophagus depicts a man with long, straight hair, and a beard wielding an eastern-style sword.
• Opening the sarcophagus will reveal that Oremor's body has crumbled to dust, but that his +1 Greatsword (in eastern style) and golden crown (150gp) remain intact.
• If the party was hear searching for a specific item from a hook, it should also be in this sarcophagus.