This was a wonderful adventure, very different from other DnD campaigns I've played or DMed in the past. I highly recommend for experienced players, maybe not for new ones.

Notes from my players

• They liked the "performative" nature of the battles. This is a unique type of combat where the crowd and the editor can have some great input and flavor on the combat. At one point, winning over the crowd meant that one of the players was seen as a crowd favorite, and had frequent requests to fight more (which gave some negotiating leverage with the Gregers).
• Not having a spellcasting character made things very difficult, and those characters tended to die more easily and be less useful. They preferred playing with at least some magic. It might be fun to find ways to add magic items for mundane characters. Things like night vision goggles and limited flame or water shaping.
• After getting indoctrinated into the style, the players loved the feeling of getting closer each session to their escape.

A few tips I recommend if you are going to DM this adventure:

• I DMed for 2 very experienced players. I don't think this setting is a good introduction to DnD because of the limiting mechanics. But for us, it was spectacular.
• It took my group 5 sessions at 4 hours each. There were 4 deaths, along with a sort of resurrection, and even more knockouts. There was nearly a total-party-kill event at the end of the first session.
• I let my players know there was a good chance of sudden, violent, and arbitrary death. Prepare at least 2 characters (one backup). I made sure we consented to this brutal and constrained style of play, and after big moments in the beginning, I kept checking in to make sure they were ok with this style. It is possible to catastrophically succeed. E.G. within an hour, one of them had sneakily robbed a guard of a set of keys. When the guards went to leave, they discovered they were locked in with the prisoners. The guards did a mass search to find the keys and executed a player. In another case, my players attacked guards in an arena fight, which triggered a boatload of arrows and no mercy.
• Create a special DM sheet. It will help you improvise critical events that are specific to this adventure. List of what mine included is at the bottom.
• Railroad the first day so they get a good understanding of the prison schedule. Have them meet the leader of the human enclave. Have them do work duty like scrubbing a ship a couple "hours" (in game, not real hours) after their first combat. My characters immediately tried to explore the caves as much as possible, which led them to not realize they had other options. They took 2 full sessions where they interacted with no prisoners, guards, or any possibility of top-floor exploration.
• Encourage metagaming. Strategic mistakes cause big problems. It made my players were more planful, and they better considered the risks and traps their actions could open up, especially when interacting with guards or leaders. Realistically in a prison setting, all they would have is time on their hands, so it's not crazy to assume they develop a sort of shorthand and mutual understanding that goes beyond spoken words. My players really enjoyed the meta aspect of this campaign.
• Don't be afraid to conspire with the players. Arrange a death or two with one of them before a session, and don't reveal it was planned until the end of the campaign. The several instances where they consented to let a character die in a planned way were the most memorable and fun moments in the campaign. But also, it sets the tone that death is familiar, which is often not the case in DnD. It causes characters to take their circumstances more seriously--a very simple analysis of "what would my character do" will likely result in death. Survival often requires compromising principles.
• Skill challenges: I learned about skill challenges from Matt Colville--search on YouTube. There are some really great escape scenes or disaster-avoidance scenes you can run with this technique. I had the annex caves ignite with explosive gas, and the players had to run a skill challenge to escape. Also, in our the final escape the players planned out, we ran it as one long skill challenge, which was exciting instead of what could have been a slog.
• Time warp: if the campaign or a session hits a lull, let a week pass and the players describe what they tried to accomplish. My characters had full explored the caves and were struggling to come up with ideas on what to do next. I let them know that between the end of session 4 and beginning of session 5, a week would pass. In one way or another, they would obtain layouts of certain rooms they targeted, details that could be helpful to them like where weapons were kept, and some chances to recruit other prisoners. I expected them to come to the next session with at least one method to escape in each of these categories: burrow, swim, climb, fight, or persuade. We started session 5 "recapping" that week's preparation when they had agreed on a plan.
• Time pressure: if you want to speed something along, let the players know that something will automatically happen within a given timeframe unless they act to alter it. E.G. if they disclose plans to prisoners of another faction, it would only be a matter of time (e.g. 2 sessions) before their plans got out and they were discovered, resulting in end of campaign and total party kill.
• Skip repetitive events after the first time. The novelty of the dwarf ghost wore off quickly--we "autoplayed" that he was still around, but otherwise skipped over interactions unless something extraordinary happened**

My custom DM sheet

• Daily food and water D20 table
• Events 4x daily D20 table
• Work duty D20 table
• Notes on quantities of guards (total = Qty of PCs x6, arena fights have d4+1 in stands, etc.)
• Factions, the quantities in them, who they are led by
• Arena weapons quantities table
• Arena Editor D4 table
• Arena auto-play injuries D20 table
• Brief table of notes on named NPCs
• Random NPC players prepared (in case players interact with unnamed NPCs)
• Table of campaign tables (e.g. Discussion topics on pg.10)
• List of all DnD skills (e.g. acrobatics), just to reinforce skill check variety
• Notes on the mechanics of rarely-used rules
  • Exhaustion Points
  • Swimming, suffocation
  • Confined space rules
  • Blindness
  • Effects of starvation / dehydration

Such a fun campaign! This was one of the first adventures I ran when I started DMing, and it is my favorite one yet by a long shot. It's so open ended that you don't need too much prep time, and the premise itself is simple enough to understand. My only complaint is that the characters themselves (the npcs anyway) aren't really that memorable. But still, super fun, would highly recommend

TLDR: Highly recommended for everyone. It's well written with many potential solutions to problems. Complete newbies might have harder time since there's no obvious easy solution to breaking out but that's really what makes the module great.

Long version: I have used this module as an introductory dungeon to my homebrew campaign. My PCs and I have played D&D before but this is my first time DMing. The module is really well written even for a starting DM like me and was tons of fun for both a new player as well as a player with 10+ years of experience.

It took us approximately 12+ hours of game to finish the module. Characters leveled up to level 3 after breaking out, they pulled off the break out on level 2.

Things I really liked about module: Good mixture of hand-holding of players and freedom. I really appreciated tables for gossips, work assignments, or arena fights; all of those came in handy. Enough interesting NPCs, I have thrown in a couple of my own from my campaign but it's not necessary. Interesting fighting modes in the arena.

Players really liked: They felt like there was plenty of options to get out, they just needed to choose one that fit their skills. They had a lot of exploring the whole place and they did, either during work assigmnents or going through the tunnels during the evenings.

Be careful: I feel that this might not be the easiest module to run for a completely new group of players and a new DM. There's little hand-holding in the actual process of breaking out of this prison and consequences are very dire if the PCs fail. TPK is actually quite possible.

Summary of our story for inspiration and for Joel :]

The PCs (all casters) have arrived in the grotto on a slavers' ship. After a short scripted sequence of being sold to Greger's family, they were send into the arena. They have made acquitance with the humans and the orcs and partially with the goblins as well. It took them about two days to explore the caves. They did two fights in the arena since joining the grotto, an intro fight and a large fight for important guests - one of the major NPCs in the story. Fast forward to how they got out, they were seriously considering to swim out through the long tunnel but were missing the necessary equipment. They have impressed Godrick very much so they used him to get some supplies, but trying to get him to get them out of the place would take some time. So ultimately, they have decided to stage a rebellion. They have managed to pacify the guard who brought them breakfast every morning and use Disguise self to disguise one of the PCs - the critical part of the plan. With some clever roleplaying and sufficient performance rolls, none of the other guards have noticed anything when the guard was returning through the tunnel to the guard room. All that was left to do, was to drop the Sleep spell and dispose of whoever was left standing. The disguised PC managed to pull that off and let everyone out. With access to keys, they have used the weapons from the prep rooms and the caverns to arm the orcs and the goblins and they stormed the upper rooms. It was the biggest fight we have ever played in our first dungeon :D, somewhere around 8 remaining hobgoblin guards including Drusus with Gregers reinforcing them on subsequent turns versus the player party (remember, all casters), supported by around 8 goblins and 8 orcs. The hobgoblin faction led by Festan was waiting on who's going to win and then either finish them off, join them or just leave. The entire escape sequence, including the big fight itself, took about 4 hours. They have originally promised to leave the grotto to Jisthelek and his goblins in exchange for their help in the riot so now Jisthelek and... one (!) remaining goblin occupy the grotto. Our adventures are now taking the human faction prisoners into the nearest town. The PCs have managed to kill Gillian but all the other Gregers have managed to flee so I am sure we will see more of them. I think they rather liked Haguur who was a very pragmatic orc and Jisthelek who was a bit nuts but fun Festan has left the grotto but they might also see more of him, especially since there are many elves on this island...

Jisthelek turned out to be the most popular character for us, they have really enjoyed his character combined with the ability to redirect attack as a goblin boss, it fit his personality perfectly.

Thank you Joel for the module!

A great little adventure and easily modifiable to fit any campaign setting! My player's really enjoyed it and it was a good change of pace from more cliche' adventures.

I know it's been some time since this was released but here's my story. I hope this finds some eyes. I played in a few games for a few sessions each, so I was a total noob. I saw a post on my school's esports team's facebook for a group of 4 friends that needed a DM. I said "eff it, let's do it." I agreed to DM and it was my first time, obviously. I only had about 20 hours of dnd under my belt at that point. I scrambled for the next two weeks to prepare and research for good campaigns to run. I decided on Greger's Grotto. My god, I am so happy I did (I'm skipping ahead, but I can run Greger's from memory now and I've done it with about 6 different groups). I DM'd with that group for a year and a half and I have Greger's to thank. That group of people are my best friends in the world now, and if I didn't have a totally kick-ass campaign to start with, I never would have made those friends. I truly thank the creator of this campaign, from the bottom of my heart, for such wonderful masterpiece. This is the campaign that changed my life. It made me into the DM I am today and totally changed my college experience. I did add a little twist after they left the Grotto though. This is the end of the review, but you can keep reading for a story. I made Jisthelek, which is weird typing it out on a public forum now, the main character of the campaign. The arcane tattoos were a curse placed on him by Asmodeus. He was originally a blue dragon that worked for Zeus to guard one of the gates to the first level of Hell. He was cursed and killed by Asmodeus and turned into a Dracolich. The special curse made him incorporate the nearest dead corpse when he died, instead of his soul returning to his phelactery. He was a lonely creature wandering the material plane for thousands of years and decided to land himself in jail (Greger's), just to check out what it was like. He had been in thousands of different bodies at that point, learning magic and other knowledge in each of them. He became my DMPC that traveled with the party. Blue Draconic Blood Sorcerer but there were some catches. You may call them OP, and I would agree, but it was fun watching the players struggle to figure out what and who he was and his past. He was able to cast spells from all classes, knew double the spells as normal, and had double the spell slots. He was able to use any die for any move that damaged or healed, but if he used more than a -1 die (so d4s instead of d6s on a fireball) he would instantly implode and die. It made for great fun as I would cast lightning bolt and roll d4s and describe the lightning bolt spell, but the fool metagamers could never figure it out. He began the campaign as a goblin, just as you wrote him, but around level 6 he died and took over the body of a red haired fighter woman. Around level 12 he died again and took over the body of a mind flayer. Around level 15 the party was on the hunt for one of the PC's mom, who was the Goddess Leira (the background made sense I promise, he was an Aasimar with a grudge against her, basically the living embodiment of Sasuke, so you can imagine the rage coming up next). She was being controlled by Asmodeus, unknown to the PCs for sure, but it was hinted heavily. The players were so invested in their characters at that point and they were dead set on killing Leira and then Asmodeus. Jisthelek, at the final moment of the fight with Leira, misty stepped behind her and thrust the Sword of Cyric through himself and her, killing them both. He took over her body (I used a homebrewed fallen angel race) and became her. He was now the BBEG, screw Asmodeus. The campaign effectively ended soon after that for other reasons, but for the 3 next campaign that my friends would take turns DMing, they would base it on my world and the lore of Jisthelek. A creature of legends, to be feared, loved, and hated. Eventually one of the PCs (Leira's son) became god level, and hunted down Jisthelek, killing him for good, taking his power, and then systematically hunted down every single dragon that existed, just to spite Jisthelek. Imagine how pissed Sasuke would be if in the moment he was about to kill Itachi, Madara came in and took his moment from him. Douche move, but I regret nothing. I am a writer, a creator. I live to invoke all emotions, and god dang what a moment that was. Greger's Grotto inspired me and grew to be one of my fondest memories, nay, my most fond memory from college. Thank you, and if there is anything else the creater of Gregor's Grotto has put out, I would play/DM it in a heartbeat.

Super fun, really thorough, detailed, and thought through, and provided players with tons of options! Also, it was easy to incorporate into my campaign.

Greger's Grotto was really flexible and provided enough options for me and my players that gameplay was fresh and dynamic without being confusing or messy. At no point did it railroad or force players into action unreasonably.

The only tiny downside is that a few of the page references are wrong. But 98% of the time they were right and very helpful! Looking up the thing only added about a minute of work, so it's not much to complain about.

A fantastically detailed adventure, highly recommended.

Greger's Grotto is a great adventure for the starting DM or new player group. The designers have included multiple maps, numbered room descriptions, story hooks, and NPCs. The module also includes various tables to generate random encounters and conditions that affect the players/arena fights/overall story. Refrence pages to the three core rulebooks (i.e. PHB 149), cutting down on time needed to search for a monster.

I used this module as a starting place for a group of 4 players (2 experienced, 2 new to role-playing games). All of the players started with level one characters and had advanced to level three by the end of the adventure. Overall, the module felt well balanced for our group. The designers do include other ways to run the adventure for higher level characters, as well as alternative story ideas.

Overall, this adventure is well written and easy to run. Highly recommended.

I DM a West Marches style game on Roll20, it is in the building stage and we have had a few test games. So I use DMs Guild to find one shot games that I can populate my DM tome with. I found this and was interested in the content. I decided to use it as a base for a new location in my game. I had to modify it to fit my world but it essentially filled in more lore and now when we get up and running, and people are DMing their own games either on Roll20 or at an actual table, Greger's Grotto might figure as a major attraction and even possibly a base for many players. Thank you to the creator for doing the hard work of creating this so people like me can use it as a resource. Keep coming out with stuff. I enjoy your work.

Used this to start a campaign as a first time DM and it was a wonderful start. Plenty of instruction, while leaving room for the DM and the players to weave their own story.

This is a thorough guide to running an adventure in really any campaign setting. It's very open and adaptable. It is completely up to you on how you initiate the adventure and it's completely up to your players on how they interact with the area presented in this adventure. Information provided is detailed down to the strength of iron bars that bar the characters escape. My players got very creative and used their spell slots on an NPC to disguise him as death and scare folks away and take a ship for themselves to escape the Grotto. I think it's definitely worth it to see what crazy shenanigans your group may get in to.