Classes that rely on the constitution as their major ability score don’t exist.
However, practically every character gains hit points and improve their constitution saving throws by having a high constitution score.
If they are harmed while casting a spell, spellcasters must additionally use constitution saving throws to keep their focus.
It’s important to remember that constitution should be a character’s second or third highest ability score unless the player is really certain that they can keep their character safe during combat.
Characters’ constitution has no bearing on their abilities, as far as I know.
Hit Points & Hit Dice
Every time a character levels up, their hit points increase the constitution modifier.
Over time, this might add up to a significant amount of money.
For every three levels of experience gained, a character with 16 Con will have an additional 30 health points than a similar character with 10 Con.
For a wizard who, on average, obtains four hit points every level, this equates to a 72 percent boost in their overall health.
They apply their constitution modifiers to each hit die that is used for healing when they take a brief rest.
Constitution Saving Throws
There are three saving throws that are more critical than others throughout the game.
Failing a con saving throw might have unpleasant consequences (paralyzed, poisoned, exhausted, blind, stunned, etc.)
I think they’re the most crucial saving throw, especially for spellcasters who have to make constitution saving throws in order to retain spell concentration if they’re damaged.
Due to the game’s creator’s desire to avoid making it too simple for PCs to inflict debilitating illnesses on the monsters, several of the game’s enemies have high constitution saving throws.
In a recent encounter, I DM’d, one of the PCs was instantaneously and permanently petrified when they failed a con save by more than 5 against a medusa’s petrifying stare.
Fortunately, the party’s monk was able to shock the medusa with his stunning blow, and the party was able to quickly dispatch the dazed medusa in under a turn.
If you fail a con save, you’re in for an unpleasant surprise!
In order to sustain their spell focus, casters will frequently look for ways to increase their constitution saving throws.
If someone is concentrating on a spell and takes damage, they must make a DC 10 or half of the spell’s damage (rounded down) saving throw, whichever is greater.
A failed concentration check results in the termination of the spell.
Taking a feat instead of an ASI, such as Resilience (Con), War Caster, or Lucky, is a common strategy.
Constitution in 5e: Final Ideas
I don’t think it’s a good idea to get rid of your constitution.
Just for the sake of having more hit points, I propose that most characters start with a constitution of 14.
Starting with a constitution of 16 or above is common for martial characters.
Additionally, barbarians are fantastic con-based characters since they suffer half-damage when they’re in a rage, thus every additional H of life prevents 2 hp from being taken away from them.