There are many, but for me I'd say my top two are:
- dropping a Yellow Mushroom in passages I've cleared in burial chambers/crypts
- and bringing my hoe to the swamp
What are some favorite tips or tricks you've used?
Edit: It's worth mentioning console/dev commands are nice to use if you've played through and are just looking to play in architecture/builder mode. Also a trick I learned on the community server I'm on is that if you build stone that touches the flat/top parts of the Stonehenge formations in the plains (not the pillars), you can build floating designs if you clear the other stones and dig down the land below (leave a little original for buffer where your stone block touches)! Super cool if you've never seen/done it, and maybe I'll get some pics once the guy is done with the build (all survival/vanilla too!).
Source: https://www.reddit.com/r/valheim/comments/stlyno/its_been_one_year_since_release_what_are_your/