So, for many things there aren’t alternatives (or active ones, at any rate). The Threadiverse userbase is presently considerably smaller than Reddit’s. Reddit has about 430 million MAU. The Threadiverse has about 50k. For every active user here, there are about nine thousand on Reddit—that limits our coverage of niche stuff.

That being said, I’d recommend looking at:

https://lemmyverse.net/communities

They spider all Threadiverse instances and build a searchable list of the communities out there.

Note that by default, they don’t show NSFW communities (you’ll need to tick the checkbox for it), which might be an issue if you’re looking for analogs of subreddits that have pictures of girls or similar.

'Course, each additional user expands the ability to cover more niches, so welcome. :-)

EDIT: You should be able to find, for example, !leagueoflegends@lemmy.world on there, but also notice that there’s very little posting outside a moderator posting the patch notes for each release.

EDIT2: You’ll get more traffic on more-general communities like !games@lemmy.world, if you’re hunting for activity, and they generally aren’t overwhelmed by traffic. But…they also won’t have the same level of focus as on communities specifically focused on individual more-niche topics.

https://lemmy.world/c/leagueoflegends

If you use the Voyager app the search bar works pretty solid to find other communities. Just start with one word or a few letters of what your looking for and then click on Communities from the list of options. From there I like to sort by Top of the Month To get an idea of which ones are the most active.

Some communities are more active than others of course. There tends to be a lot of people subscribed to many communities, but there may be fewer people currently posting to one or another community.

If you want more of anything then posting about it is a surefire way to build upon interest here.

Welcome to Lemmy, we’re a little all over the place but in a fun way I think.

1. There’s a piefed NSFW instance. Google it.
2. !football@sopuli.xyz
3. maybe !Space@mander.xyz ?
4. Again, probably need to go general. Try !gaming@lemmy.world

Check “all” from time to time, search community listings, and be ready to pounce on a community that sounds interesting if someone mentions it in a comment anywhere. There are far too many created communities for the number of users, so aiming a tier more general than you think you need to is often a good idea.Then, frankly, a lot of interesting discussion happens in generalist communities that happen to post something (often a meme) relevant to someone’s interests.