Combat rating 8
1 Cyclops (CR 6)
2 Owlbears (CR 3)
Combat rating 9
1 Cyclops (CR 6)
1 Galeb duhr (CR 6)
Combat rating 11
1 Cyclops (CR 6)
3-4 Merrow (CR 2)
2 Giant sharks (CR 5)
Combat rating 12
2 Cyclops (CR 6)
3 Sea hags [coven] (CR 4)
How to use
The first thing I would like to note is that the one eye is a weakness. The original cyclops in The Odyssey was given one eye as a weakness for Ulysses to exploit, and its only significant function in the story is Ulysses taking advantage of it. (I thought of being more specific, but I decided to avoid spoilers.)
What does this mean for you? Aside from the very limited range of the cyclops throwing due to poor depth perception, I would be very sympathetic to any ideas your players might come up with to take advantage of it, or to hinder the cyclops eyes in general. For example, if they use their shields to reflect light into the cyclops eyes, I would let it blind him for a round (at least the first time.) I would also think that the cyclops would have disadvantage on the saving throw for Color Spray, and any other blindness inducing spells.
Combat Encounter 1: Giant Bowling (difficulty 7)
Starting the Scenario: The players spot an opening in the cliff face and decide to enter. The room inside was once, a very long time ago, some type of temple, but that time is long past. There are still several [I suggest four] pillars holding up the ceiling, and perhaps the players will spot fragments of mosaics, all that’s left of the mosaics that once decorated its walls. Aside from that the room is empty, except for a number of animal droppings, and perhaps a large sack of straw, so large that it would take at least eight people to carry it if you didn’t want it dragging on the floor (the cyclops’ bedroll.)
It could be that the entire party will enter, especially if it’s near the end of the day. Alternately, you can have them discover a large chest, easily their own height, tucked away in a corner of the cave. Due to difficulty in opening it, the rest of the party will probably be called in.
Not long after the party enters, the cyclops arrives. He rolls a huge boulder into the entrance, they preventing them from leaving easily (there is still some room between the top of the boulder and the roof, so they could climb up and out,) and he stands on the far side of the boulder. As soon as it’s his turn in the initiative order, he picks up a boulder and hurls it at them.
Cyclopes Strategy: While his chances of hitting them aren’t high (assuming they’re more than thirty feet back. The cavern goes at least sixty feet back) any stones that miss are going to smash straight into the back wall, or even worse, into one of the pillars. The first time that a stone hits the back wall, the cave shakes, but there is no actual effect. After that, though, pieces of the wall and the roof will collapse each time. I would say that each miss reduces the size of the battlefield by a little, [say five feet (1 square) by 2-3 squares in length to start with, perhaps a bit more as the battle progresses,] and a pillar being knocked down turns the area around the destroyed pillar into difficult terrain and increases the amount of cave destroyed by later rocks.
If a PC is standing in the area that’s going to get destroyed, they take 2-3 d8 bludgeoning damage from falling stones and they become pinned to the ground. They can spend an action to try to get out on their turn, but will take a STR check [I would suggest DC 10 the first time, and increasing it each time as the battle progresses.] If they pass the check by five or more, it only costs them a bonus action instead of an action. Other players can also take an action to remove the stones, thereby freeing the trapped PC or reducing the check by five.
When a pillar is destroyed it won’t pin them, but they might take an extra d8 of damage. If most of the pillars are destroyed, the room caves in. [See below.]
Players’ limitations: If they want to climb onto the boulder at the entrance and fight the cyclops in melee, there are a couple of ways you can run it. To start with, as the boulder is high, climbing it might take an action and require a skill check to achieve. (Either athletics or acrobatics, their choice. DC 10 with both hands free, DC 12 with one hand free, DC 14 with both hands full.)
Further complications can be: 1) Unstable footing, if the cyclopes hits them they have to make a save [STR or DEX, their choice. DC following the rules on concentration checks.] to avoid falling right back down. 2) The entrance is only so big, and if one player stands on the stone, nobody else has line of sight on the cyclops. (At higher levels, you could have two cyclopes as another option, one of whom stands back and continues to throw. That would raise the encounter level to difficulty 9.)
Cave Collapse (Failure Scenario): If the cave collapses, everybody takes significant bludgeoning damage [probably around 6d8]. At least one of the characters should avoid being trapped by rocks, and he’ll have to find a way to dig the others out. The cyclops is in the area, but not actively looking for them, so they’ll have to be careful not to make too much noise. Alternatively, perhaps one player will distract the cyclops while another digs them out. In the end of the day, both the DM and the players will need to improvise somewhat.
Combat Encounter 2: Fight Along the Cliff Face (difficulty 8)
This can be used as its own encounter, or as a continuation of the previous encounter. If they drove the cyclops back during the previous encounter, possibly with a spell or by destroying the barricade, you may want to have the cyclops retreat and move on to this encounter. Alternatively, if they killed the cyclops in the last encounter, you could have his brother show up for revenge the next day.
Scenario Battlemap: The cave opens onto a ledge, 10 feet from the ground. The ledge runs in both directions, but it’s somewhat narrow, so that one PC can’t stand behind another.
The cyclops is standing in front of the ledge, but he can hit them while they’re on the ledge due to his height. (Don’t believe me? The hill giant is 16’ feet tall, according to the Monster Manual. Since the cyclops is one CR higher, it seems logical that he’d be at least as tall.) (You could have the cyclops stand five feet back from the ledge, in which case most melee attacks wouldn’t be able to hit him. Personally, I prefer not to use this strategy here [we’ll say that the cyclops doesn’t realize this.] Partially, this is because I don’t want the players to be motivated to jump down. Partially, this is because the encounter is already hard enough. And partially, I have plans to use this strategy once the blog gets up to giants.)
The cyclops isn’t standing right in front of the cave, so they can’t hit him with a ranged attack or spell from inside the cave (I would consider stating that the sun’s glare gives them disadvantage if they try to make a ranged attack from just inside the cave. Alternatively, you can have the cave entrance at an angle, pointed the wrong way.) If they decide to run in and out, the cyclops can use one of its attacks to smash the ledge in front of the cave. Entering and exiting will still be possible, but it will take some careful climbing to reach the ledge.
To prevent them from jumping down, let them know that the area at the bottom is covered by water. [It’s possible that when they entered, the tide wasn’t in, but it is now.] Jumping down will mean making a DEX save [DC 14] to keep their feet, with 2d6 slashing damage from the rocks and them being dragged out by the tide for 5-10 feet before they regain their footing. They’ll also be fighting in water if they do that. [This doesn’t give the cyclops disadvantage, as his arms are above the water.] If they start to move to shore, you can choose to have a rock move under them, or to have them slip on a rock. They’ll need another DEX save to avoid falling prone.
There is no obvious way down from the ledge. Getting to the cave will have involved climbing. (If this is the cyclops’ home from the previous encounter, provide him with a very large rock outcropping that he uses as a stepping stone to get up. Both during the last encounter and when entering or exiting his home.)
Cyclops’ strategy: In addition to the difficulties from the ledge, the cyclops isn’t fighting carefully. Perhaps because of his poor depth perception, perhaps because he’s so angry at the PCs (whether for invading his home, killing his brother, or other.) Sometimes his blows hit the back of the cliff, causing either rubble to fall [and inflict damage] or for sand to fall, blinding the PC for a turn. Other times he hits the ledge, smashing bits of it and leaving missing pieces that the players will have to jump over if they want to cross.
(If the players have the idea of hiding in the cave and waiting for the tide to go down, or for the cyclops to leave, you could switch to the previous encounter, assuming they haven’t already fought that. Another thing the cyclops might do is to go back to the shore, take something flammable, light it and put in into the cave, to smoke the PCs out. Before you do this, you might want to have him waiting outside for a while, and have him pace back and forth, so the players don’t run away while he’s getting the wood.)
Combat Encounter 3: The Boat and the Cyclops (difficulty 8)
The Scenario: The players are trying to reach an island, for whatever reason. They have a small sailboat or rowboat that they’re using, probably bought or rented, with nobody on board except themselves. As they approach the island, the cyclops that is there sees them and takes exception to their coming [or maybe he just decided that this is the easiest way to capture them] and begins throwing boulders at their boat.
I would suggest a sea that isn’t stormy, but neither is it completely calm. There is a good beach for them to land on, but that’s where the cyclops is standing, and attempting to land there will give the cyclops 3-4 rounds in which to attempt to sink them. [He won’t even have disadvantage on the last 1-2 rounds.] (What happens if he does sink them will be discussed below.)
The other option is around the side of the island*. Unfortunately, this isn’t a nice sandy beach. In fact, it is basically a rocky outcropping. Landing the boat here will require great skill.
The Players’ Options: Ask the players to choose between concentrating on guiding the boat through carefully and concentrating on avoiding the cyclops’ boulders. They can’t do both, as guiding the boat safely means keeping it going straight and watching that it shouldn’t get caught on the rocks, while avoiding the boulders means steering the boat away from the general area of where the boulder is going to land. By the time someone can work out whether the boulder is going to hit them or going to miss, it’s too late to steer the boat away. [It’s up to you whether you want to let them know about the cyclops poor depth vision. This will undoubtably affect the decision, but it won’t necessarily make the decision.]
If they focus on steering the boat, you’ll roll for the cyclops’ boulders each turn. What to do if one hits them will be discussed later. They can choose between landing fast and landing carefully. If they choose fast, they land that turn [the cyclops only has a chance to throw one boulder] and the STR check to land successfully is DC 16. They can add a proficiency bonus only if one of them has the sailor’s background, or if they have some other reason to have sailing experience. [The PC will the sailor background doesn’t have to be the one with the highest strength. They can work together to share their bonuses. That said, only add one PCs strength modifier to the roll.] If they choose carefully, the cyclops gets two chances to throw boulders, but the DC is 12-13. Everything else is the same. Landing details will be discussed soon.
If they concentrate on trying to avoid boulders, you don’t have to roll for the boulders, as they automatically miss. [You most definitely should narrate the boulders, however, or they’ll feel cheated. You might want to fake-roll, where you roll the dice behind the screen and then, regardless of the outcome, tell them how the boulder was flying at them but they managed to turn the boat away.] You’ll use a DC 13 STR roll [proficiency as discussed above], with best two out of three rolls deciding [to make it seem like it’s taking a while, especially important because of the cyclops and its boulders.] If they fail twice, they capsized [see below.] If they succeed twice, they reach the land and are ready to land the boat.
Landing on the Beach: If they aim for the beach where the cyclops is, they won’t require any special skills or rolls to land. After all, that’s the easy beach. What they will need is to pull the boat up onto the beach if they don’t want to lose it, while fighting a cyclops at the same time. I’d suggest that mooring the boat require 2 players with a combined STR modifier of + 4 [ignoring negative modifiers]. Pulling the boat to safety will use up their actions for that round. It can also be moored by any three players. If not done by the end of the second round, their boat is already on its way out to sea. They’re going to have to find a different way off the island.
Landing on the Rocks: If they aimed for the rocks, landing will be harder. The only two way I know if to land on rocks without wrecking your boat are 1) One person with a rope climbs out of the boat and onto the rocks. The other end of the rope is tied to the boat. He pulls the boat in while the others fend off any rocks that might wreck the boat. 2) They drop an anchor offshore. They hold onto the rope, at first keeping the boat close to the anchor but gradually letting out more and more rope so that the boat slowly reaches the shore.
The second method takes time, and is therefore non really relevant in this case. (If they want to go for it, the cyclops will have 4-6 turns to try to hit them with a boulder.) I would suggest that they choose a PC to help reel in the boat. That PC will have to make a DEX skill check [climbing, which is acrobatics] followed by a STR skill check [athletics]. Both checks are DC 13. If they fail the DEX check, they fall against the rocks, taking 2-3 d8 damage [a mix of bludgeoning and piercing damage.] This also slows them, giving the cyclops another chance to try to hit them. [Even if they were dodging before, they can’t do it this close to the rocks.] If they fail the STR save, they take 1-2 d8 damage from being forced off their feet, and they have to try again next turn. In the meantime, the cyclops continues to try to hit them.
If the Boat Sinks: If their boat gets sunk, you have several options to choose from. 1) They have to make a successful STR check [athletics, DC 12] to swim to shore. Every turn that they fail, they gain a level of exhaustion. If they fail three times in a row, they either automatically succeed or they get washed out to sea, your choice. [If you choose washed out to sea, you might want to send a merfolk or a dolphin to rescue them, eventually. They probably won’t rejoin the party until after the cyclops encounter, and possibly it will take even longer.] 2) They have to make the previous skill check to stay together. Anyone that fails ends up on a random spot on the beach, possibly with one level of exhaustion. [If exactly one person succeeds, ask him who he’d like to end up next to.] Other possible penalties would be to take a few d8 damage from the rocks, if they chose the rocky shore, and/or to miss the first round of combat as they get their breath back. 3) They get to the beach without incident. Possibly the cyclops is waiting for them, and possibly he left. Of course, they have no food, little to no fresh water, and no way to get off the island.