Q: Is Messenger used on a complex series of flybys – the spacecraft flew by Earth once? ¶
A: Yes, and Venus twice, and Mercury itself three times, allowing it to decelerate relative to Mercury using minimal fuel.
Q: Was Messenger among the numerous space assets that imaged Comet Encke and Comet ISON? ¶
A: Yes, As its orbit began to decay in early 2015, MESSENGER was able to take highly detailed close-up photographs of ice-filled craters and other landforms at Mercury's north pole.