Oh, nice. Otherscape looks fire. I'm familiar with PBTA and tags in other games. What do you mean PBTA-like but tab-based? Like are there moves, but they are based on the tags?
So I don't know PBtA much - this comes from what people tell me about it and then comparing that to OtherScape and Legend in the Mist.
Your character in the 'Mist' games (OtherScape, Legend in the Mist, and partially City of Mist) has no numeric ratings on the sheet (this is partly false - the sheets do have a 'status ranking' box somewhere to track when you get something like a stacking condition).
There's no ancestry/species/race, no class, no levels, no feats, skills, etc.
Just tags. Essentially a one sentence single line description of something.
In game, as you do things, you roll dice using the PBtA method, and add in tags that either give you a bonus or penalty to the roll. Any tag that fits the situation can be added. The only way to 'advance' in the game is to find ways to add your negative tags.
So you might have tags like:
- "back alley hacker"
- "cyberspace AI contacts"
- "known hacker"
In hacking a government database in Cairo - you could trigger all 3 of those for a net +1 to you roll by roleplaying that you're hanging out in a cafe in some slum based market, talking to your AI friend based out of Sudan who wrote an old version of the database you're breaking into, but the government of the country it's in is slowly closing in on your alias.
And then the GM might add in a situation tag:
+ Working for a Cyber Djinn
A magical Djinn from cyberspace hired you, and gave you enough details to get an edge on this mission.
So you roll your PBtA 2d6, and add 2.
In any given situation, you'd be running down your tags and seeing which ones fit the current narrative of the roleplay, and then triggering those for a die roll. That is done instead of looking at attributes, skill lists, class abilities, and so on.
Even combat works like that. If you get hit it might apply a tag of 'torn leg muscle' - and now any roll involving your legs has a penalty. Stack that penalty (and penalties that are close enough to be relevant - like say "bleeding out" and "concussion" or whatever up to 6 and your character undergoes a 'permanent alteration' - which might be getting killed, or it might be whatever fits.