Probably a recurring theme, but here’s the first 4th edition D&D rule that we’ve been doing wrong
1. You only roll once to attack, even when you’re about to Critical.
It looks like we skimmed the rules around this section, or we read them and then forgot them, or we just plain got them confused. When you roll to attack, if you roll a 20* then you automatically hit. You also have the chance to cause a critical hit. The determination of whether it’s a critical hit is simple. Does your total attack roll score enough to hit. If it does, you criticalled, if it doesn’t you still hit, but for regular damage.
So if the enemy AC is 23, and you roll 20, and add 2 for a total of 22, you hit but don’t crit, if your total turned out to be 24, you would have caused a crit instead. This gives you the chance to hit something 1 in 20 times that you might never otherwise be able to hit, and also gives you an increasing chance to crit against creatures as you increase your attack bonuses off of that automatic hit.
Let me know if I’m still wrong 😉
* A 20 is always an automatic hit, some weapons have an increase critical hit range (19-20), if you roll a 19 and the total is enough to hit, you crit, but if you roll a 19 and the total is not enough to hit, you miss and don’t crit. Only a natural 20 is enough to automatically hit, no matter what the weapon.