The user can drastically increase the gravity in a given area, making moving or even standing difficult for anyone in it, possibly causing damage to the targeted area/targets, prompting the ground to crack and cave in, crushing the targets.
Several Characters (Kingdom Hearts) via use of the Gravity spell
Gravity Man (MegaMan 5)
Galaxy Man (MegaMan 9)
Megaman (MegaMan 9); after defeating Galaxy Man
Jolene Gina Dewar-Molotov (Nexus Wars)
Pokemon capable of using "Gravity" (Pokémon)
Sonic the Hedgehog/Violet Void (Sonic Lost World)
Granzon/Neo Granzon (Super Robot Wars)
All Crushers (The Candy Shop War: The Arcade Catastrophe)
Hiram Worchester (Wild Cards)
Bluenote (Fairy Tail) uses the Fall spell on Happy.
Issho (One Piece) uses his power to increase gravity on one point to pin Law to the ground and immobilize him with his sword.
Many of Brago’s (Zatch Bell!) spells such as Gurabirei create a gravitational field around the enemy, forcing them to the ground. Brago’s bookkeeper, Sherry decides how heavy the force is by how much energy she chooses to put into the spell.
Koichi Hirose's (JoJo's Bizarre Adventure Part 4: Diamond is Unbreakable) Stand "Echoes Act 3" using its signature ability, "3 Freeze" on Yoshikage Kira's "Sheer Heart Attack"
Sugou Nobuyuki/Oberon (Sword Art Online) has pinned Kirito and Asuna down with gravity magic.