There are multiple superstars involved in this game. But look for defense to carry the day. 
There were a combined 194 points scored in Game 5 of this series. The Thunder-Rockets combined for 204 points in Game 6. Now we've reached Game 7 where the intensity should be at its peak. So I'm not expecting a scoring explosion, nor an up-temp, fast-paced game. 
The Rockets have a history of not producing their expected total during the later stages of a series. The Under has cashed 79 percent of the past 28 times the Rockets have played Games 5 through 7 in the postseason. 
Houston thrives on firing up 3-point shots. Only two teams ranked higher than Oklahoma City in 3-point field goal percentage defense.