What if instead of dealing double damage, maximum damage, or a random injury from a critical hits table, a natural 20 means the character gets an extra action (that may be used for an extra attack if so desired)? If that action results in a natural 20, another extra action is granted, and so on. In this case, each natural 20 offers a choice and the potential to make combat more interesting.
I think it's worth playtesting.
RPGaDay situation: My answers for this year's RPGaDay are succinct enough that I decided to continue my tradition of posting them daily on Twitter and collecting them into a single article at the end of August or the beginning of September. If you wish to read them on Twitter, my handle is @Cuparius.
RPG I've played most often in the last year or so: Mutant Crawl Classics RPG
RPGs I've GMed most often in the last year or so: Dungeon Crawl Classics RPG and Ghostbusters 1st edition
Board game I've played most often since the beginning of 2020: Don Quixote
RPGs I most need to run in the very near future: Ghostbusters, Dungeon Crawl Classics RPG, Teenagers from Outer Space
Other RPGs I want to run as soon as possible: Savage World of Flash Gordon (Savage Worlds), Awfully Cheerful Engine! RPG, Zorro: The Roleplaying Game.
Thing I need to adapt to RPG for a friend: Tron
Missed deadline due to annual forgetfulness: One Page Dungeon Contest 2022
Ironclad goal for this year: Publish my first zine.
