What we really need to do is start writing down all the Lemmy instances. It's one thing to tell off reddit, it's another thing to get people off of reddit.
Mod reminder: We do have a rule against brigading. I know this is a special case - but please keep it respectful if you are planning to represent the Fediverse on r/place.
In my opinion, something like "Join Lemmy" is fine, but a giant penis with LEMMY next to it is not as good a look and I'd rather you not coordinate that plan here.