What is THAC0? TO HIT ARMOUR CLASS ZERO - or -
T-o
H-it
A-rmour
C-lass
zer-O.
An enemy wearing full plate armour and a shield is zero. numbers greater than zero (1,2,3...) are assumed to be weaker armour, numbers below and into the negatives (-1,-2,-3) are assumed to have even stronger armour. Thac0 is the number needed to hit someone in full armour+shield. Whilst this seems like an odd way to work combat out, it’s not as mad as you might think.
As a 1st level character, your Thac0 is 20. Meaning a roll of a d20 would have to get a 20 to hit someone with an AC0 (armour and shield). If the enemy had an armour class of 5 (for example: chain mail), you would need a roll of 15 or more.
As you level up, your Thac0 levels with you, meaning you become more proficient in your combat. For example: at level 4, a warrior has a Thac0 of 17, meaning anything rolled above a 17 will hit someone in full plate and a shield.
You can increase your roll with modifiers such as being proficient in a weapon, or having tactical advantages or conditions. For example: attacking from the rear gives you a +2 to your roll, meaning a level 4 warrior could roll a 15 (normally a failure against AC0) but then adding the +2 means it would be a hit.
How combat works:
SHIELDS
You can choose to use your shield (if you have one) against a single attack. That renders the enemy attack roll useless, saving yourself the damage. However, once a shield has been used – it is splintered and thus useless.
SURPRISE
Surprise can sometimes occur. A 1d6 is rolled and if it lands on a 1 or 2, that constitutes as that individual or party as being surprised. If they are surprised, they receive one round of damage with no resistance. Players would also lose any AC bonus upon the effects of that attack.
CRITICAL HITS & FUMBLES
Critical hits occur when you roll a natural 20. Critical falures (fumbles) occur when you roll a 1. After which, a d100 is rolled to determined a special success or failure.
A saving throw can be used against multiple things – for example: Paralysis, Poison, or Death Magic. Rod, Staff or Wand. Petrification or Polymorph. Breath Weapon. Spells.
Your throws are determined by level. To make the save, you roll 1d20 vs your saving throw score. If the result is equal or greater than your score, you succeed. For example, a level 6 Wizard has a score of 13 against poison. Meaning 1d20 with a result of 13 or more will successfully render the poison useless. Whereas a roll of 12 or under would render them poisoned.
When a character reaches 0 hit points, they are rendered unconscious and fall to the ground. They will be wounded and thus bleeding out.
If they reach -10 hit points, they will die.
If the players use one round tending their wounds, the character is revived at 1 HP. It is worth noting that a monster can still attack a downed person.
Characters heal naturally at 1d3 hit points per day of rest. Rest is defined as low activity, such as riding a horse or travelling from one person to another. Strenuous activity such as fighting, lifting heavy things, or running away in fear, do not constitute as low activity.
Players can expedite their healing with magical potions or visiting a practitioner of magic..
Sometimes characters will have to rely on their skill checks in order to accomplish a task. If you have professional background that may aid in a task, the difficulty level shall be reduced to give advantage. In this system, we are using Xd6 skills tests. These are when you roll x amount of d6 vs your ability score. For example, a difficult check against your STR 8 would mean you'd need to roll under 8 on 4d6.
What if you want to perform a more challenging task? Then you will have to rely on TWO of your skill checks in order to accomplish a task. These are when you roll x amount of d12 vs two of your ability scores. For example, if you wanted to do a complex long jump / oil flask toss move. You would roll vs both your dexterity (the jump) and your strength (the throw).
Experience is awarded in many ways. The table below summarizes some of the common ways players can earn XP through combat, treasure discovery, role-playing, and exploration.
Total the sum of how much XP all PCs need to advance from the start of the level at which they are currently to the next level. That number is constant until a PC gains a level. When a PC achieves a feat, the entire party is awarded the percentage listed of that total. Divide that number by the number of players present during the session to arrive at the per-PC share.
Award Type | Description | XP Value |
---|---|---|
Combat Awards | Defeating a Monster | XP will be related to monster type. |
Rumour | Confirm a rumour's veracity. | 2% |
Quest | Complete a quest | Minor 5%, Major 10% |
Location | Discover an important location | 5% |
Trap | Overcome a trap | Minor 2%, Major 5% |
Puzzle | Solve a puzzle | Minor 2%, Major 5% |
Secret | Find a secret or interpret hidden lore | 2% |
Faction | Manipulating or crippling a faction to your benefit | Minor 5%, Major 10% |
NPC | Interact beneficially with an important NPC when stakes are at play | 5% |
Lore | Apply in-world lore in a useful or flavorful manner | 2% |
Haven | Establish a reliable safe haven | 10% |
Explore | Explore at least five areas of a single dungeon level | 2% |
Skills | Use equipment or abilities in an unorthodox yet useful manner | Minor 2%, Major 5% |
Hazards | Surmount an environmental obstacle or hazard | Minor 2%, Major 5% |