Zen Pinball

Next to the left bumper near the flippers, you can see the word "SLASH". These letters light up one by one after you hit either Ryu's or Genshin's ramps outside of a ramp combo. Just shoot them, wait five seconds so the combo ends and shoot the next one.

Once you light up the entire word, a red light saying "OBLITERATION" will light up in front of Ryu's figure. To get the ball up there, you must perform the jumps from the Jump ramp.

After shooting the Jump ramp, smash your flipper repeatedly until you're across both jumps. Ryu's figure will then cut your ball in two and you just got yourself an obliteration. Perform two more to start the Karma challenge and the trophy will unlock (you don't have to play the Karma challenge).