[RPG] What do I do when the enethe has an AC higher than 20

combatdnd-5e

I'm very new to this game and am wondering, If the enemy has say 30 AC with all his equipment and buffs, what would I have to roll to hit him since I have to roll a 20 sided die to determine if I hit or not? Since 20 sided dices obviously don't go to 30 I'm curious as to how this work.

Best Answer

Attack bonuses are your friend.

Based on how you're attacking your target, various bonuses will be added to the roll.

If a spell, your spellcasting modifier and your proficiency bonus (PHB p.205). If a weapon, either your strength or dexterity modifier (based on the weapon and, possibly, your choice) and your proficiency bonus if you're proficient with that weapon (PHB p.194).

Then there are various circumstantial bonuses that might apply: bardic inspiration from your friend, the effects of a bless spell, the enchantment-based +2 of a magic weapon, a fighting style, &c.

30 is hard to hit, no bones about it. But a bless (2.5 avg bonus) and a 5th-level bardic inspiration (4.5 avg bonus) and a +1 weapon and your level 5 proficiency bonus of +3 and an ability modifier of +4 gives you a +15 attack bonus; you'll hit 30% of the time. Not great, and it takes some resources to get there, but it took the target some resources to get to 30, too.

So are critical hits.

Remember that a 20 on an attack roll always hits, regardless of AC. That may seem a stretch, but advantage and luck dice can significantly improve those chances. From 5% to ~10%.)