Hogwartz: From the Ashes
Half-blood is the term commonly given to wizards and witches who have a Muggle/Muggle-born parent and magical parent. By the 1990s, half-bloods were the most common type of magical person, as the wizarding population would have become extinct had they not inter-married with Muggles and Muggle-borns.
Due to the dominance of the magic gene, children born to at least one magical parent will almost always be magical themselves. A non-magical child born to a Muggle and a wizard is considered a Squib (not a Muggle).
WIZARDS AND HALF-BLOODS
Those who believe in the importance of blood purity consider half-bloods to be inferior because of their Muggle heritage, though superior to Muggle-borns. Occasionally the term “half-blood” can be used in a derogatory manner, similar to the epithet “Mudblood”; Bellatrix Lestrange and the portrait of Walburga Black did so on multiple occasions.
Some half-bloods expressed prejudice towards those with Muggle heritage, despite having some themselves, and clung to what wizarding heritage they had. Notably, Lord Voldemort hated Muggles and Muggle-borns, despite having a Muggle father, and denied his half-Muggle heritage, leaving hints that he was a pure-blood instead, emphasizing his heritage to the famous pure-blood ancestor, Salazar Slytherin, to make himself more believable. Severus Snape may be another example; his self-entitled nickname was “Half-Blood Prince” because his mother, Eileen Prince, was a pure-blood witch and his father, Tobias Snape, was a Muggle. However, Remus Lupin reported that he never used the nickname openly. This, as well as Snape’s membership in the Death Eaters, suggests he may have been ashamed of his Muggle heritage, at least in his early life. In fact, these people, along with some other Death Eaters, pretend to be pure-bloods, hiding their Muggle heritage from anyone else; most of them are half-bloods due to centuries of dilution and decline of what may be called as a true “pure-blood”. Ironically (or perhaps because of), regarding the Prophecy concerning his defeat, Voldemort chose to go after a half-blood Harry Potter instead of the pure-blood Neville Longbottom.
When the Ministry of Magic fell under Voldemort’s control in 1997, Muggle-borns were openly persecuted and pure-bloods were favored above all else. Half-bloods were still accepted at Hogwarts School of Witchcraft and Wizardry, but were not treated as well as the pure-blood students.
Ability Score Increase. Your Intelligence ability score is increased by 1, and you increase any one ability score of your choice by 1.
Age. Half-Bloods are humans, and have the same age and maturity.
Size. Half-Bloods are of average human weight and size.
Speed. Your base walking speed is 30 feet.
Languages. You can speak, read, and write English and one other language of your choice.
Brave. You have advantage on saving throws against being frightened.
Fast Learner. Whenever you gain a level in an arcane spellcasting class, add one spell of a level you are able to cast to your spellbook or list of spells known.
Lucky. When you roll a natural 1 on an attack roll, ability check, or saving throw, you can reroll the die and must use the new roll.