Originally Posted by
Talyn
The ruleset is all the coding under the hood that lets FG know what actions and dice rolls are supposed to do. The CRB is the reference material (here are the classes, the races, the ancestries, the feats, spells, items, etc.) you'd build your characters and NPCs with. There is no SRD yet for the PFRPG2 ruleset yet (estimated six months before they arrive) so of course you can play for "free" — you'd be spending the time to input all that data yourself (pro tip: just input the little bits you actually need to play right away then slowly add the rest as you go along) vs. spending the money where someone already did the work for you (and as features get added to the ruleset, the CRB will be updated for free to support those new features).