D&D 4e: Core Mechanics

Rolling

Types of Dice

d4, d6, d10, d12, d20

DiceRoll Notation

3d8 + 5				## roll d8 3x times, then add 5

Percentages

Roll 2 d10s. One for the double-digts, one for the single-digts.
If both rolls are 10, the result is 100%
otherwise, if the double-digit dice-roll is a 10, it is equal to 0
This is to prevent percentages above 100%.

Always Round Down

No matter what the statistic, if you end with a fraction of a number, you always round down (even if you would mathematically round up).

Specific beats General

Specific rules beat general rules.

Gameplay Modes

Exploration

The gameplay is built entirely around exploration leading to encounters. During Exploration, the DM sets the scene and the players can decide what to do. It may be a group decision to go down a path, or a crowded area, bar etc. Movement here is not grid-based, it's more subjective as to what the DM lets you do. Exploration is typically not turn-based, players can just say what they are doing until the initiate an encounter.

Encounters

Encounters occur during exploration, or in dungeons. Typically, the DM awards XP for a successful encounter.

combat encounters		turn-based attacks
noncombat encounters		traps, puzzles, obstacles. Can bargain, use magic, wits etc.

Actions/Checks

Actions require checks to determine their rate of success. The DM decides on a number, the player rolls a d20. The player adds the modifiers from their character sheet/items. If the player rolls higher than the target, their action is successful.

Check Types
Attack Rolls		Attacking anything.
Skill Checks		Knowledge/Skills/Talents player has acquired can be used arbitrarily. (ex: identifying a monster)
Ability Checks		Anything that isn't an Attack, or a Skill Check is considered an ability check. DM decides the relevant ability, and the DC required for the task to succeed. (ex: breaking down a door)

Every action a player can make is tied to one of the 6 ability scores. Performing a check involves:

• rolling a d20
• adding your Ability Modifiers (( ability_val // 2 ) -5)
• adding any equipment modifiers
• Comparing it against the DM's decided Difficulty-Class points.

If you score higher than the DC, your action is successful. A single turn for all players is considered to be a round. One round represents 6s in the game world.

movement

Game Board

The game board is made up of 1" squares.