Virtual Tabletops
AboveVTT is an extension for dndbeyond (available for chrome and firefox), it uses your dnd beyond owned content to let you easily populate battlemaps with official monsters, recently they also added content from Open5e, more on that later, giving you more options for monsters.
Owlbear Rodeo v1 or Owlbear Rodeo v2, two versions of the best system neutral VTT im aware of, v2 does have payment options but if you're vigilant about the files you have saved the free 200MB should be plenty.
V1 is going to be removed on July 18th 2023, but the developers have promised that V1 will be open sourced and self-hostable in the future.
Sounds and Music
Tabletop Audio is a massive filterable stockpile of ambience and music for all kinds of vibes and situations, they also have a built in soundboard, one of which can be customized. they have a patreon which gives you access to alternate takes of most of their sounds and early access to new ones but whats there is still plentiful.
Tabletop RPG Music has a narrower selection that Tabletop Audio, and more of it is locked behind patreon but whats there is more purely music focused.
Kenku is a pay what you want self-hosted discord bot that helps you play music from anywhere on the internet or saved locally on your pc through a discord voice chat. Setting up the bot is easy and the website has a walkthrough on how to do it.
Monsters, Combat, and Encounters.
Kobold Plus Club is a website made to replace the fantastic kobold fight club, a 5E resource that lets your easily balance and create encounters with randomized or hand-picked monsters, you can also add homebrewed or third-party published monsters using google sheets, json files, or csv files. The KPC discord has a large backlog of sources made for official monster books not on the site and a fair amount on 3pp monster books.
Improved initiative is a website that connects with KPC but can be used independently, it's a combat tracker that shows you the relevant monster statblock for that monsters turn and lets you apply damage and healing to monsters. Improved initiative only gets full statblocks for creatures available on open5e by default.
open5e is a collection of official 5e ogl and third party ogl content. there are extra races, subclasses, monsters, and spells available here for free. this sounds like a piracy website but its not, kobold press, one of the third party publishers featured on the site even links to it in some of their products. the only downside of this site over the paid products they come from is the lack of art.
Maps
!battlemaps@lemmy.world a community right here (well, right there since its on another instance) on lemmy for sharing battlemaps, please respect that community's rules if you participate there.
Dungeon Scrawl is a webapp that lets you create old-school style maps there's a fair few paid features, the main one being multiple map saves at once, but there's enough there to create and decorate maps quickly and easily.
Dungeon Generator is another tool made by the creators of kobold plus club. It randomly generates entire dungeons floor by floor and lets you export the in various formats. you can even cycle the styles of rooms if they're close but not quite what you want.
Miscellaneous Other Things
Fantasy Name Generators has a massive selection of name generators, not only fantasy npcs but also real life names from various cultures, k-pop bands, religious orders, diseases, daycares and just about any other thing you might need.
Chartopia is a website that lets you easily create and share rollable tables for loot, encounters, names or anything else you can need a random table for.
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