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Murphy thrashed Neil Robertson 10-2 in last year's final and faces Mark Allen in the first round on Sunday.
"Everyone wants to beat the world champion and defending champion of an event," Murphy told BBC Sport.
Five-time champion Ronnie O'Sullivan returns to tournament action and faces Mark Williams, while world number one Neil Robertson plays Marco Fu.
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O'Sullivan, who recently compiled the 800th century break of his career, has not taken part in the main draw of a  tournament since losing in the quarter-final of the 2015 World Championship.
He did take part in qualifying for the German Masters in December, but suffered a shock defeat by Stuart Carrington.
Murphy became only the 10th player to complete the Triple Crown of World Championship, UK Championship and Masters after his success in London last year.
"I go into all the events now as someone who has won the Triple Crown," he added. "That is a very exclusive club of some very good players. To be in the group and to be the most recent addition is something I am extremely proud of.
"Seeing the trophy everyday and being introduced everywhere as the current Masters champion is a great feeling."
Shaun Murphy believes he is a marked man as he begins the defence of the Masters crown at Alexandra Palace.