Later Kunti chose the handsome Pandu as her husband in a swayamvara. Bheeshma arranged the weddings of both Kunti and Maadri in a manner suited to their rank and race.
It was the golden age of the Kuru house. Pandu went on a tour of the entire Bharatavarsha. He re-established the supremacy of the Kuru house, won fame for himself and was claimed to be the best soldier of his times. After the campaign, Pandu with his two queens, went to the forest for relaxation. He spent many happy days with his two young wives. Later it was the memory of these pleasure-filled days that kept Kunti alive.
In that forest lived a rishi with his wife. The two were intensly in love with each other. As they wanted to enjoy the pleasures of love without restraint, they changed themselves to a couple of deer! Pandu saw them while they were coupled together and as they were easy targets, shot at them with arrows. This heinous action proved to be fatal and the rishi cursed Pandu: 'when, overcome with love, you approach your wife, death will come to you even as it did to me'. Fate had struck Pandu in his happiest moment and at the peak of his life. (As also the Rishi and his wife, who had lost themselves in their idyllic love and were indiscreet.)
(This shifting of humans to the other forms is the staple of the stories in paranormal novels)
Pandu full of self-reproach and remorse decided to renounce his worldly ways and chose to live in the forest like a hermit and do penance. On hearing this news, Bheeshma who had been free from the responsibility of running the kingdom had to rule again and felt that he had become impervious to all hurts.
(My first thought was how can a 'Rishi' freak out this way! Checked the meaning of 'Rishi'. My sanskrit dictionary says: An inspired poet or sage. A sanctified sage, an ascetic,anchorite.
Encarta has this: rishi --South Asia Hindu sage: a Hindu who is revered for holiness, religious knowledge, or piety --
sage-- wise person: somebody who is regarded as knowledgeable, wise, and experienced, especially a man of advanced years revered for his wisdom and good judgment.
Well, an 'inspired poet' can be expected to loose himself the way the rishi did! Our rishis were admirable, they knew how to play and how to do penance and acquire power!)
(Multi-tasking abilities were obviously handed down by our rishis!)