Gnome

The following information was sourced from the Player's Handbook.
A constant hum of busy activity pervades the warrens and neighborhoods where gnomes form their close-knit communities. Louder sounds punctuate the hum: a crunch of grinding gears here, a minor explosion there, a yelp of surprise or triumph, and especially bursts of laughter. Gnomes take delight in life, enjoying every moment of invention, exploration, investigation, creation, and play.

• Ability Score Increase. Your Intelligence score increases by 2.
• Creature Type. You are Humanoid.
• Age. Gnomes mature at the same rate as humans, and most are expected to settle into adult life around the age of 40. They can live to 350 years on average, but it's not too uncommon for them to reach 500 years of age.
• Alignment. Gnomes are generally Good. Those who tend towards Law are sages, engineers, researchers, scholars, investigators, or inventors. Those who tend towards Chaos are often minstrels, tricksters, wanderers, or fanciful jewelers. Gnomes are light-hearted, and even the tricksters amongst them favor harmless pranks over vicious schemes.
• Size. Your size is Small.
• Speed. Your base walking speed is 25 feet.
• Darkvision. Accustomed to life underground, you have superior vision in dark and dim conditions. You can see in dim light within 60 feet of you as if it were bright light, and in darkness as if it were dim light. You can't discern color in darkness, only shades of gray.
• Gnome Cunning. You have advantage on all Intelligence, Wisdom, and Charisma saves against magic.
• Languages. You can read, speak, and write Common and Gnomish.

Forest
As a forest gnome, you have a natural knack for illusion and inherent quickness and stealth. In the worlds of D&D, forest gnomes are rare and secretive. They gather in hidden communities in sylvan forests, using illusions and trickery to conceal themselves from threats or to mask their escape should they be detected. Forest gnomes tend to be friendly with other good-spirited woodland folk, and they regard elves and good fey as their most important allies. These gnomes also befriend small forest animals and rely on them for information about threats that might prowl their lands.

• Ability Score Increase. Your Dexterity score increases by 1.
• Natural Illusionist. You know the Minor Illusion cantrip. Intelligence is your spellcasting modifier for it.
• Speak with Small Beasts. Through sound and gestures, you may communicate simple ideas with Small or smaller beasts.

Rock
As a rock gnome, you have a natural inventiveness and hardiness beyond that of other gnomes. Most gnomes in the worlds of D&D are rock gnomes, including the tinker gnomes of the Dragonlance setting.

• Ability Score Increase. Your Constitution score increases by 1.
• Artificer's Lore. Whenever you make an Intelligence (History) check related to magical, alchemical, or technological items, you can add twice your proficiency bonus instead of any other proficiency bonus that may apply.
• Tinker. You have proficiency with artisan tools (tinker's tools). Using those tools, you can spend 1 hour and 10 gp worth of materials to construct a Tiny clockwork device (AC 5, 1 hp). The device ceases to function after 24 hours (unless you spend 1 hour repairing it to keep the device functioning), or when you use your action to dismantle it; at that time, you can reclaim the materials used to create it. You can have up to three such devices active at a time. When you create a device, choose one of the following options:
• Clockwork Toy. This toy is a clockwork animal, monster, or person, such as a frog, mouse, bird, dragon, or soldier. When placed on the ground, the toy moves 5 feet across the ground on each of your turns in a random direction. It makes noises as appropriate to the creature it represents.
• Fire Starter. The device produces a miniature flame, which you can use to light a candle, torch, or campfire. Using the device requires your action.
• Music Box. When opened, this music box plays a single song at a moderate volume. The box stops playing when it reaches the song's end or when it is closed.
• At your DM's discretion, you may make other objects with effects similar in power to these. The Prestidigitation cantrip is a good baseline for such effects.

The following information was sourced from Mordenkainen Presents: Monsters of the Multiverse.
Deep Gnome
Deep gnomes, or svirfneblin, are natives of the Underdark and are suffused with that subterranean realm’s magic. They can supernaturally camouflage themselves, and their svirfneblin magic renders them difficult to locate. These abilities have enabled them to survive for generations among the perils of the Underdark.

• Ability Score Increase. Your Dexterity score increases by 1.
• Gift of the Svirfneblin. Starting at 3rd level, you can cast the Disguise Self spell with this trait. Starting at 5th level, you can also cast the Nondetection spell with it, without requiring a material component. Once you cast either of these spells with this trait, you can’t cast that spell with it again until you finish a long rest. You can also cast these spells using spell slots you have of the appropriate level.
• Intelligence, Wisdom, or Charisma is your spellcasting ability for these spells when you cast them with this trait (choose when you select this race).
• Svirfneblin Camouflage. When you make a Dexterity (Stealth) check, you can make the check with advantage. You can use this trait a number of times equal to your proficiency bonus, and you regain all expended uses when you finish a long rest.
• Languages. You can speak, read, and write Undercommon.

Homebrew Changes
Changes to the Languages trait for Deep Gnome: Addition of Undercommon as a known language.