Final Fantasy 15 Chapter 5 offers two dungeons, starting with The Hexatheon's Blessings, Fociaugh Hollow and The Trial of Ramuh. Have Chapter 4 is done and dusted to get this started.
The Hexatheon's Blessings
Recommended level: 21
Follow Umbra into the woods, and when the cutscene is over make your way north along the road. You're without a car for now, so it's worth resting up before you leave partly to avoid wandering about in the dark, and partly because it gives you a fast travel point as you'll need to double back later. While you're here, we'd also recommend ticking off the Friends of a Feather quest so can rent a Chocobo if you haven't already - which will make the coming journey across Duscae much easier and faster.
You'll eventually encounter two groups of Imperial soldiers - the first is blocking the road with an MA Veles mech, and the second are in the woods by the side of the road. Head up the grassy slope from the second group and touch the first runestone.
Keep heading north, restock at Alstor if you need, and then head towards the next marker - you can either cut directly cross-country or follow the road towards the Alstor Slough parking spot and take the path.
Head back towards Wiz Chocobo Outpost, and take the narrow muddy path up the slope. As you head upwards you encounter a group of Imperial troops, so deal with them, use the nearby campsite if you need it, and then enter Fociaugh Hollow.
Need more help? Our Final Fantasy 15 guide and walkthrough can provide tips on main story, as well as the open-world's many quests and activities. Learning how to get AP fast, EXP fast and money or Gil fast will aid you in many optional dungeons and tombs - including how to open and explore their locked doors. There's also plenty of interesting side-quests, too, such as the Scraps of Mystery and Professors Protege frog locations. And if you want to get around easier, you can rent a Chocobo, learn the infinite sprint trick and later in the game, get the flying car Regalia Type F. There's also more to see and do with DLC, such as Episode Gladiolus and Episode Prompto.
Fociaugh Hollow and The Trial of Ramuh
Recommended level: 22
Head towards the narrow opening at the far end of the first chamber, squeeze through, and then deal with the Imps that appear as you round the bend. From here the dungeon is fairly linear, so simply work your way through taking out the pockets of resistance as you go.
Eventually Prompto will wander off, and as you enter the next area you'll be facing two Mindflayers and a handful of Imps and Goblins, but the area is much more open than your previous encounter with Mindflayers which makes the fight much easier.
Carry on towards the marker, and when you enter the large cavern to the north of the map take the western pathway. Naga will appear, and regardless of how you answer her question you're in for a boss battle.
Naga boss battle
This battle is largely an endurance affair, and most of her attacks are easily avoided or parried, but the danger comes from the clouds of green smoke she exhales - getting caught in one will turn you into a toad and leave you unable to attack, block, or use any items. She's vulnerable to broadswords, daggers, ice, and royal weapons, and resistant to ice, so pile on those attacks to seek victory.
Once you've worn her down touch the last runestone then leave the cave. Chapter 5 isn't over yet though - continue on to Engaging the Empire and Aracheole Stronghold so you can get your car back and continue back on the open road.