I'm a brand new player and I want to clarify my attack sequence as simple as possible. I'm a level 1 Rogue, so I have 1d8 "hit dice" according to the rules.
How does that affect me if I'm making attacks with my daggers? What would my attacks look like? For a main hand and off hand, as far as I know it's 1d4 + 3 for main and 1d4 for off hand, does this sound correct? Where does the hit die fit into it?
My DEX mod is +3 and proficiency is +2.
Your Hit-Dice have nothing to do with your attacks, and are related to your HP max and HP recovery while resting. They're "hit dice" as in "hit points", not as in "hitting enemies".
Roll 1d20 + 3 (dex mod) + 2 (proficiency)
If this roll is greater than target's Armor Class, you hit. Roll for damage:
1d4 (dagger damage die) + 3 (dex mod)
This amount is subtracted from the enemy's HP, provided they have no special defenses.
Roll 1d20 + 3 (dex mod) + 2 (proficiency)
As before, if this beats target AC you hit. Damage changes though:
1d4 (Dagger damage die)
On the second (off-hand, if you will) attack, you do not add your dex mod to the damage.
As a rogue, you may have access to a Sneak Attack - this can only apply to one of your attacks each turn.
Advantage or Disadvantage will make your d20 attack rolls work differently. For Advantage and Disadvantage you will roll twice and use the better or worse roll, respectively.
Hit dice do affect your ability to survive hits. The name originally referred to the dice you might roll to determine your hit point maximum, and in 5th edition it also describes a healing mechanic.
In the miniature wargames that inspired D&D, when two squads or units of men fought, you rolled dice to determine how many of the enemy minis were killed. Each was one "hit", and a strong or lucky unit might deal several simultaneous hits to an enemy unit.
Chainmail (1971), a wargame by D&D creator Gary Gygax, introduced hero characters (meant to represent characters like Legolas or Gimli), who fought as effectively as an entire unit of men on their own. Hit points did not exist, so heroes could not be killed unless they took a certain number of simultaneous hits.
Original Dungeons & Dragons (1974) introduced the notion that characters might instead be killed by cumulative hits, a concept we today know as hit points. You rolled dice (originally 1d6) at character creation and each time you leveled up to determine how many hit points your character could take. This was known as dice for cumulative hits, or later hit dice.
This remained the status quo in D&D until about D&D 4th edition (2008), which made game balance a priority. Designers decided that rolling randomly for your hit point total was too unbalanced, since a few lucky or unlucky rolls could make your character extremely strong or weak for their level. The standard method was now taking average of your hit dice rounded up, so that a character who might gain 1d8 hit points upon levelling up would simply gain 5.
D&D 5th edition (2014) sought a return to tradition. Hit dice returns to its original meaning, although you automatically have maximum at first level (e.g. your rogue will always have 8 + Con modifier hit points at first level, rather than 1d8), and each time you level up you can still choose to take the average rounded up (e.g. you can gain 1d8 + Con modifier to your hit point maximum, or 5 + Con modifier).
Slightly confusingly, hit dice are now also used as a separate mechanic for healing during short rests between combat.
This harkens back to the healing surge mechanic of 4th edition which sought to remove the reliance on cleric spells for healing between combat, since in 3rd edition clerics were often treated like a healing battery. The healing surge in turn derives from the reserve points 3rd edition variant used in designer Mike Mearls' Iron Heroes, a low-magic D&D variant without clerics, so player characters needed some ability to heal themselves between fights.
Essentially, hit dice in 5th edition are now a reserve of healing equal to the dice you would roll if you rolled randomly for hit points, which you don't actually do at first level any more for balance reasons.
With regards your attacks, your character would roll 1d20 + 5 with both daggers to see if they hit, dealing 1d4+3 damage on a successful hit with the primary weapon, and 1d4 on a hit with the secondary weapon. In the Player's Handbook, see p.194-196 for the rules on attack rolls, melee attacks, two-weapon fighting and damage, and p.186 for the rules on spending hit dice to heal.
Hit dice is a representation of your maximum Hit Points (HP) that are gained every time you level up, as well as HP recovered every time you do short rest (if you choose to use your hit dice(s) to heal damage taken).
You gain one hit dice every time you level up. That dice gained is the appropriate hit dice for the class you level up.
Example:
If you are a level 1 Fighter, you have one d10 hit dice. If you level up you can choose:
- another Fighter level, then you are level 2 Fighter with two d10 hit dice.
- other class, like Wizard, then you become level 1 Fighter/level 1 Wizard, with one d10 hit dice and one d6 hit dice.
For more information read "Multiclassing: Hit Points and Hit Dice" in page 163 PHB
When you do a short rest, you can spend your hit dice to recover Hit Points. The amount of HP recovered is the number you rolled for every hit dice, plus CON modifier.
Example:
If you are level 1 Fighter/level 1 Wizard, you can choose to spend either the one d10 or one d6. You roll the desired dice, and you recover HP equals to number rolled plus your CON modifier. For more information read "Resting: Short Rest" in page 186 PHB
Your attack is determined fully by rolling a 1d20 and adding relevant modifiers to the roll, and then comparing that score with the Armor Class (AC) of the target. If the total equals or is greater than the AC, your attack hits and then you roll for damage, which fully depends on the weapon you use.
Example:
You are attacking an enemy with a dagger. You roll 1d20. You then add your proficiency bonus to the outcome and DEX mod. In your case, you add total of +5 bonus attack roll.If the result is equal or more than the enemy Armor Class (AC), then you roll for damage. Dagger use 1d4, plus the highest of your STR or DEX modifier. In your case, it should be +3 bonus to damage.
For more information read "Making An Attack" in page 194 PHB
Note that you never use your Hit Dice for the attack.
In the case of two weapon fighting, using two daggers, according to page 195 PHB:
Two-Weapon Fighting (Combat Rules)
When you take the Attack action and attack with a light melee weapon that you’re holding in one hand, you can use a bonus action to attack with a different light melee weapon that you’re holding in the other hand. You don’t add your ability modifier to the damage of the bonus attack, unless that modifier is negative. If either weapon has the thrown property, you can throw the weapon, instead of making a melee attack with it.
Your first attack will deal 1d4 + DEX mod dmg, then your offhand attack will only deal 1d4 dmg.
If you have the Two Weapon Fighting Style from Fighter or Ranger, your offhand attack will deal 1d4+ DEX mod dmg like the main hand attack. Either way, your attack roll will still use 1d20 + proficiency bonus + STR/DEX mod (whichever higher).
