This is pure speculation but I think that biomes need to be big enough to spawn certain things, so if they're very thin or "peppered" around another biome they won't spawn those things because they don't have enough space. I say it because I was in a map where I had a huge meadow continent with very small patches of black forest which didn't spawn trolls or dungeons and even copper was very rare. Tin on the other hand, was plentiful because just a small patch near a river and I had like 3 or 4 veins.
Same happened with the swamps. I had to sail far to find the first one, but it was too small. Until I walked deep enough for dungeons to start spawning and managed to find 3 in the same big area.

Now I changed maps and I have big biome areas and everything is plentiful. I've even been able to build several smelters because now I'm not sort on cores.

We had a similar issue until we sailed 2-3 continents away from the Pillar Spawn Island. The farther away it seems we got from our starting island the more prolific Sunken Crypts became. If I was to give someone starting out advice, it would be do not build a massive headquarters on the starting island. Find a meadow that borders or is near multiple biomes. Make sure there is lots of swamp with lots of crypts and a large mountain (or multiple) biome with drakes & golems. Our best bases were at one time dilapidated Draugr villages in meadows along a shoreline. They came with multiple buildings, and repairing them saved us a tonne of resources. They were also on reasonably flat land, so the amount we had to level and terraform was extremely minimal. Doing a lot of terraforming & levelling on what became our main base dropped our framerates so much that we rarely ever go there anymore. Gardening & fending off invasions are extremely frustrating, as movement is way to choppy. We call it Lagwagon Base now.

Originally posted by katsuragi:

How rare are these? Will you get enough Iron to progress if there is only one crypt in your entire world? I've fully searched 7 swamp areas and have not seen one crypt yet. It's a mausoleum looking building with an iron gate for a door, right? Some green torches burning outside? I don't remember them being this hard to find when I played a year ago.

There are 2 types of swamps. Those that do have crypts, and those that don't. Swamps that do have crypts are usually quite big.

Originally posted by SiEgE:

Originally posted by katsuragi:

How rare are these? Will you get enough Iron to progress if there is only one crypt in your entire world? I've fully searched 7 swamp areas and have not seen one crypt yet. It's a mausoleum looking building with an iron gate for a door, right? Some green torches burning outside? I don't remember them being this hard to find when I played a year ago.

There are 2 types of swamps. Those that do have crypts, and those that don't. Swamps that do have crypts are usually quite big.

thank you. that checks out because the 1 i finally found was in the largest swamp yet, furthest from the center

there is a fixed number of sunken crypts in every seed. i cant remember the number but its lots. theres NO way an entire seed will only have one sunken crypt

so far there have been 0. I've searched a pretty huge area altogether. I'm as confused as you are
also,,, it seems like when you die you only lose your progress to the next skill level? I think you used to lose 10% or 20% of your total skill levels which really sucked. But'ive died twice now and none of my skills went down. just the next level progress got cleared. Do I have that right?

https://vgtimes.ru/uploads/posts/2021-02/thumbs/1613045749_crypt_1.jpg

Try to find a big swamp. In my world, I managed to find a huge swamp in which there are about 15 crypts, by the way, after one of the updates, the scrap metal in them was updated!

Originally posted by katsuragi:

so far there have been 0. I've searched a pretty huge area altogether. I'm as confused as you are

have you used the seed viewer?

Originally posted by Amargo:

https://vgtimes.ru/uploads/posts/2021-02/thumbs/1613045749_crypt_1.jpg

yep, that's the way I remember them looking. None of those anywhere

Originally posted by katsuragi:

How rare are these? Will you get enough Iron to progress if there is only one crypt in your entire world? I've fully searched 7 swamp areas and have not seen one crypt yet. It's a mausoleum looking building with an iron gate for a door, right? Some green torches burning outside? I don't remember them being this hard to find when I played a year ago.

1. Can you provide the seed ID for your map please?
2. Crypts should not be rare on decent sized swamp biomes on a map. Number can vary of course.
3. There should never be only 1 crypt on an entire world. That is an exaggery unless you have a bugged world.
4. 7 searched "areas" doesn't necessarily denote the size of those areas. If they're just a few pixels in size, chances are there's no crypt obviously(though still possible).
5.It is a stone rectangualar structure in the swamp with a locked iron gate with green torches yes.

It will probably take 3-4 to get you past swamp boss and to next biome, more if you want more armor and weapon selections. The same for later tier armor.

If it doesn’t matter to you, then I can give you 300 metal, I started a construction site, but then changed my mind)

ok I finally found one, half inside one of those huge horizontal swamp trees (the indestructible kind). Couldn't even see the torches until I was facing it from just the right angle, which only happened because I was running for my life from one of those new "stump spiders" or whatever they are.
"7 areas" would be look at your map, determine the average amount of space a continuously connected swamp takes up, and multiply that by 7. that's about how much swamp I searched just to find 1.
However, if they are all hidden half inside other objects now, I've probably overlooked a few as I haven't been scrutinizing things that seemed to be giant swamp trees.

Originally posted by katsuragi:

ok I finally found one, half inside one of those huge horizontal swamp trees (the indestructible kind). Couldn't even see the torches until I was facing it from just the right angle, which only happened because I was running for my life from one of those new "stump spiders" or whatever they are.
"7 areas" would be look at your map, determine the average amount of space a continuously connected swamp takes up, and multiply that by 7. that's about how much swamp I searched just to find 1.
However, if they are all hidden half inside other objects now, I've probably overlooked a few as I haven't been scrutinizing things that seemed to be giant swamp trees.

Again, please provide the map seed ID, we can then use: https://valheim-map.world/ ...

and see if there are any discrepancies with what you're stating concerning your issue.

Each world contains many, many, many crypts.
I have never seen, on the over one hundred plus seeds I have looked at, none. The number may be randomized within a parameter. But never have I seen a seed absent of Crypts.
Nor have I seen one where the number of Crypts was alarming in that way. And that is exactly the kinds of things I want and intend to notice when doing a comparative analysis.
Unless it's bugged. There will be (ballpark) nearly 50 on any given map. You have just not had very good luck yet. Keep looking, they will come like rain. Swamp is large, not the largest biome on Avg, but very spread out, some can be vastly extensive, or oddly isolated patches. Keep looking!