Open ended d20s
if you roll a 20 which wouldn’t already be a successful check, you roll d10 (numbered 0 – 9) and add that result to your original 20. if you get a 9 on the d10, you roll it again (and potentially again and again, as long as you keep on getting 9s) and add all the d10 results together, along with your original 20.
similarly, if you roll a 1 which, with modifiers, isn’t a failure, roll d10 and subtract your d10 result from your 1.
these rules supercede the “20 always hits” and “1 always misses” rules.
rules for criticals are basically unchanged, except that a roll of 20 which (with additional rolls) doesn’t hit the target isn’t (of course) eligible for a crit.
does that make sense?
return to Table Rules