I've actually been thinking about how to run a more involved game on the blockchain.
That's cool, I'd love to hear your ideas. Steem posts are suited to the play-by-post style but I think that style would not be attractive to many. I'm going to review what @simplegame has done so far now.
I had a couple of ideas before which involved exploiting the 7 day editing window for a Steem post, that springs to mind as an effective way to craft a "scene" (or whatever appropriate game building block) without spamming the chain, and while commit data to record as it goes.
In terms of integration you cannot call external services in Roll20 even though you can write scripts, and I couldn't find anything similar for Fantasy Grounds. I'm doing a little research on some smaller scale open source tabletop platforms that might be applicable instead.
Regarding @v-entertainment are you talking about Way Finder?
You do know that doing an edit to an existing post within the seven day window creates a relatively hefty blockchain transaction every time you do it, right? And every time that you do it, a client reading posts on the blockchain is required to go through all of the blocks which have been committed since the original post creation time looking for update transactions so that it can have an actual coherent view of a post to present to a reader.
Editing posts is one of the worst things that you can do if your interest is to keep the number of transactions and amount of data and which is needed to be transferred by the witness servers low. They hit hard not just when they change their committed, but for ever after whenever that post is read.
As hefty as a new post, it's technically a rewrite. Clients do not piece edits together, the current version is stored in witness node DB and there is a particular endpoint which just serves that.
In terms of "blockchain spam" it could be pretty bad though, true. I am more thinking about client level spam though, take a look at @simplegame and you'll see what I mean.
One of the things that goes into the blockchain is that you're subject to data bandwidth limits, so you probably want a hybrid on-off system.
Any software used would have to be designed more or less around Steem or whichever blockchain you want to use as your main method, though you could ostensibly have a client/server setup in which nodes only handle game-related content (which isolates you from general purpose networks and avoids spam).
IIRC it should be possible on Steem to make JSON entities that don't appear as posts but can be displayed in special ways; Steem Monsters does something like this, if I am thinking right.
Way Finder is what I was thinking of. I don't remember if that was the one I was looking for or not, but it's the one that I was able to recall today.