The Dark Tower Wiki

Sombra Corporation is a company that serves the interests of the Crimson King, their insignia is a cloud with a thunderbolt coming out of it. Its primary focus is owning real estate and also owns Trans Corporation

Sombra Corporation's insignia, as seen on the Todash Bag in Discordia

Sombra tried to purchase the vacant lot from Calvin Tower. They paid him $100,000 in return for a promise that he won't sell the land for a year. Eddie Dean got to Tower before the contract ran out and convinced him to sell it to the Tet Corporation instead.

Sombra also responsible for setting a trap for Father Callahan. They promised to give Callahan's homeless shelter a million dollars if they came to headquarters. Richard Sayre sprang the trap on Callahan and meant to use vampires to infect him with AIDS. Callahan decided to jump out the window rather than allow that to happen.