game's playfield multiplier advances at 0.5X per loop completed, and the amount of time each step of the multiplier remains active gets shorter until 4X (which is 10 seconds long). With Doctor 6, the playfield multiplier advances by 1 instead of 0.5, again to a maximum of 4X, and the time for each step of the multiplier lengthens. Additionally, every 10th loop enables the Sonic Boom, which reroutes the ball back to the left inlane. The player can then hit the W-H-O shots (right ramp, left entrance lane, upper right loop) in order to earn 10 million per shot. Doctor 7: Center target bank and mini-playfield (The Time Expander). Without Doctor 7, each hit on the row of 5 targets on level 2 of the Mini-Playfield lights a single Time Expander Factor (15 of which are needed to start multiball). With Doctor 7 enabled, each hit on these targets counts double. Additionally, if Doctor 7 is collected, hitting the center target while the mini-playfield is on Level 1 will light a Time Expander Factor, and if the player fails to score a jackpot during the first wave of multiball, the center target on level 1 will add more time to the re-lock timer. Multiball The Multiball mode in Dr. Who begins after the player lights 15 Time Expander Factors after locking the ball. After the Time Expander reaches 0, the mini-playfield rises again to level 3, which has three gates in it with a small picture of a Dalek on the front. The player must shoot one of the doors to start multiball. Once the player has done this, the mini playfield lowers, releases the two locked balls, and then rises again back to level 3. To earn the jackpot, the player must hit all three gates on level three of the mini-playfield. This awards a jackpot that begins at 5,000,000 points for the lowest tier of Daleks and grows dramatically as the player rises through the ranks of Daleks (up to the Emperor Dalek at 50,000,000 points). After the player defeats the Emperor Dalek, Davros is revealed as the arch-villain behind the story. The mini-playfield lowers itself back to Level 2, and to defeat Davros, the player must hit the bank of 5 targets once (more if the player has already defeated Davros) to deactivate Davros' shield and get the mini-playfield to raise back to level 3. Once Davros'