Garnet have a high tolerance to pain. It makes her not fazed to getting damage. While not outright invincible, it is shown that Garnet is more physically durable than Pearl or Amethyst. It is shown that she endures different levels of damage almost daily, withstanding falling cars, scuffles with Jasper, and various other forms of physical force.
Gauntlet Proficiency: When channeling the collective power of the universe through her gemstones, Garnet can summon a pair of gauntlets. Garnet is highly proficient when using her gauntlets and is extremely skilled in hand-to-hand combat. She can deal massive strikes that can deal a heavy amount of damage and deliver swift blows with lightning speed. Garnet's gauntlets have had spiked brass knuckles added onto them.
Rocket Gauntlets: Garnet takes aim with her gauntlets and shoots them as projectiles in "Watermelon Steven". In "Reformed", after Garnet launches her gauntlets, her hands are detached from her body, and her gemstones are moved to the stubs of her arms.
Weapon Size Augmentation: Garnet can increase the size of her gauntlets, easily quadrupling their size, and deal increased damage at the cost of reduced speed. This was hinted during "Garnet's Universe". Being an imaginary story, that means Steven knew about that power before the real debut in "Warp Tour".
Deflection: Garnet can use her gauntlets as shields as seen in "Onion Trade" to deflect a volley of Dave Guys. They are also used in "Catch and Release" to block Peridot's electrokinetic discharge in Amethyst's whip, although it is unknown whether Garnet simply prevented the electric current using her gauntlets or absorbed it with her electrokinesis.
Shock Wave Emission: As seen in "Gem Harvest", Garnet can pound her gauntlets into something and create a shock wave strong enough to make something, such as carrots, fly out of the ground.
Photokinesis: In "It Could've Been Great", Garnet can be seen using Photokinesis, an ability she shares with Pearl, Ruby (Doc), Ruby (Eyeball), Peridot, and the Rutile Twins. This might be a power that every Gem can use or a power inherited from Ruby.
Gem storage: Garnet has the ability to materialize different items out of her gemstone(s), similarly to Pearl. In "Serious Steven", she summoned the key to the Pyramid Temple and in "Giant Woman and Love Letters", she summoned her goggles.
Fusion Realm: In the episode "Mindful Education", Garnet was shown to have helped Stevonnie gain a deeper connection to themself; the way this was done was apparently through a quite easily gained meditative state in which Garnet guided Stevonnie throughout. When Garnet and Stevonnie entered this realm Garnet apparently showed Stevonnie how to keep in touch with themself and how to gain a deeper understanding of both their sides and how to resist falling apart by being honest to themself.
Future Vision: Garnet can see multiple future outcomes and probabilities with her third eye. This includes extremely unlikely and ridiculous outcomes, as a considerable amount of her available visions depict Steven's (and possibly other individuals') demise at the hands of mundane tasks or objects on a regular basis. Future vision must be used consciously and takes some time to use, as Garnet has been shown in a thinking position when activating it. During that time, someone can alter the future, as seen in "Marble Madness", when Steven ruined the plan to learn about Peridot by going up to her while Garnet was still using future vision. Garnet must also consciously seek out specific details and judge which possible futures are most probable, which means she can overlook some possibilities, such as Pearl deceiving her in "Cry for Help". Garnet's visor improves her clarity and focus while using future vision, but she can still use the ability with it off, as demonstrated in "Reunited" when she foresaw the Diamonds' arrival.
Garnet's future vision comes from Sapphire, as confirmed in "Keystone Motel", although Sapphire's future vision is different from Garnet's. Due to Sapphire's passive personality, she can only see one future where she does not intervene. Garnet has Ruby's impulsive influence, so she can see multiple futures where she does intervene.
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Garnet, kissing Steven on the forehead and transferring her Future Vision powers.
Temporary Power Transfer: In "Winter Forecast", "Jail Break", and "Future Boy Zoltron" it is shown that she can temporarily pass on her future vision ability to others through lip contact. While Garnet has only been seen using lip-to-forehead contact to transfer her power, it is unknown if this is the only method. As she has only been seen sharing her power with Steven, her affection could say bias on how she chooses to transfer the power.
Heat Resistance: Her invulnerability is often displayed in her extreme resistance to heat, from when she had scalding-hot coffee splash onto her without flinching in "Future Vision" to when she left to retrieve the Earth Beetle (which required her to swim in active lava) in "Giant Woman". It has also been said that she could swim in the core of the Sun and survive. This may be because of Ruby's thermo-regulation.
Enhanced Calculations: Garnet mentions her ability to sense structural integrity in "Cheeseburger Backpack".
It is currently unknown whether this is a unique power, a separate portion of her heightened senses like her future vision, or just a simple observation.
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Electrokinesis: Garnet can generate electricity, as seen in "The Message" when she used it to charge the battery of Greg's van, "Catch and Release" when she was tangling with Peridot, and "Arcade Mania" when she restarted "Meat Beat Mania" after Steven unplugged the game. Garnet has this ability due to the combination of Ruby's pyrokinesis and Sapphire's cryokinesis.
Electric Resistance: Garnet is impervious to electricity, as seen in "Future Vision" when she easily deflected a lightning bolt that was about to hit her and Steven with her gemstone. It is seen again in "Catch and Release" when she stopped Peridot's electricity from traveling down Amethyst's whip, only to send her own electricity back at her.
Electric Jump: In "When It Rains", Garnet uses her electrokinesis on the offensive for the second time, generating electricity and releasing it on impact with the ground, where the energy then travels to the target. This particular move is long-ranged.
Super Speed: In "Arcade Mania", Garnet karate chops the inner arms of the Gem Cave Creature and shakes Meat Beat Mania's ham controllers at incredible speeds. In "The Message", Garnet quickly places couch cushions around the Wailing Stone. In "Bismuth", Garnet engages Bismuth in combat with an immensely fast approach. She inherited this ability from Sapphire.