This is the half giant I once made for my Dark Sun game. I found that it worked fairly well. Any character I saw built with it seemed to me to be about as balanced as a RAW character. That being said, I only had a chance to play a few Dark Sun games. I got to level 4 with one group and level 9 with another, so the highest level half giant character I saw was 6/3 (was a fighter).
Half-Giant
Ability Score Increase: Your Strength score increases by 2. Your Constition score increases by 1.
Size: Half-giants vary in size from 10 to 12 feet tall and weigh up to 1,600 pounds. Half-giants are considered to be large in size. As a large creature, you can carry, push, drag, or lift double what a medium sized creature of your strength can physically manipulate. In combat, you control a 10 by 10 foot space and can squeeze into a 5 by 5 foot space (spending 1 extra foot for every foot of movement taken, suffering disadvantage on attack rolls and Dexterity saving throws, and granting advantage to any creature that is attacking you while you are squeezing into the smaller space). You can be surrounded by up to 12 medium sized foes, and you take up 1 ½ “units” when surrounding an adversary. You can wield large sized weapons without taking disadvantage to your attack rolls. You, however, take disadvantage when attacking with a weapon that is not sized for a large creature. You also may not wear any armor or clothing not designed for your size. Armor and clothing designed for a half-giant costs twice the normal price and weighs twice as much as normal. Finally, you must eat and drink 4 times the quantity of rations required by a medium sized creature and pay 4 times the normal lifestyle expenses.
Speed: Your base land speed is 30 feet.
Giant Heritage: You are considered to be a giant.
Giant’s Strength: You have advantage when making Strength checks to break an object.
Half-Giant Toughness: Your hit point maximum increases by 1, and it increases by 1 every time you gain a level.
Mercurial Nature: The magic that allows human and giant blood to coexist leaves the half-giant’s personality naturally unhinged. As a result, you suffer disadvantage on any saves versus charm based effects. In order to counterbalance this mercurial disability, half-giants will often attach themselves to the personality of a friend or mentor, mimicking their personality traits, ideals, bonds, and flaws in order to somewhat reorient their own persona. At the start of every day, you may choose one member of your party to mimic. For that day, you take on their personality trait, ideal, bond, and flaw as well as your own.
Sluggish Mind: Half-giants are not as quick witted as their human counterparts. A half-giant must begin play as a member of the “half-giant racial class” (see below). The half-giant racial class only has 3 levels. You must level this class to level 3 before multicasting. After you have leveled the half-giant to level 3, you must multiclass into another class, and you must meet the multiclassing requirements of that class.
Languages: You can speak, read, and write one language of your choice. It is strongly advised that you choose common.
Half-Giant Class Features
Hit Points
Hit Dice: 1d10 per half-giant level.
Hit Points at 1st Level: 10 + your Constitution modifier.
Hit Points at Higher Levels: 1d10 (or 6) + your Constitution modifier per half-giant level after 1st.
Proficiencies
Armor: Light armor, medium armor, heavy armor, and shields.
Weapons: All simple weapons.
Tools: None.
Saving Throws: Strength, Constitution
Skills: Choose one skill from Animal Handling, Athletics, Insight, Intimidation, Perception, and Survival.
Equipment
You start with the following equipment, in addition to the equipment granted by your background:
• (a) large kank vest or (b) large leather armor, large sized light crossbow, and 20 large wood tipped bolts.
• (a) a large bone simple weapon.
• (a) a large shield or (b) a large stone simple weapon.
• (a) 4 dungeoneer’s packs or (b) 4 explorer’s packs.
Ham Fisted
At 1st level, your unarmed attacks deal 1d4 damage. If you get an improved unarmed damage die from any other source (such as the monk’s “Martial Arts” ability or the “Tavern Brawler” feat), you instead deal double the normal damage dice. For example, a half-giant with the “Tavern Brawler” feat deals 2d4 damage.
Boulder Toss
At 2nd level, you become proficient in tossing large boulders at foes. If you can find a rock-like object of at least 300 pounds, but that weighs no more than your maximum carrying capacity, and both your hands are free, you may use an action to pick up the rock and make a thrown ranged weapon attack against a foe. This attack has a range of 60/240 feet. If your attack hits, it deals 1d12 + your Strength modifier damage. At 5th level, the damage increases to 2d12 + your Strength modifier. At 11th level, the damage increases to 3d12 + your Strength modifier. At 17th level, the damage increases to 4d12 + your Strength modifier.
Giant’s Endurance
At 3rd level, you learn to focus yourself to shrug off injuries. As a reaction when you take damage, you can spend a hit die. Roll that hit die and add your Constitution modifier. Subtract the result from the damage you take. After you use Giant’s Endurance, you cannot use it again until after a short or long rest.