As you may know, the ascendant (or cusp of the first house), the point that rises to the eastern horizon at the moment of birth, is a big deal in astrology. It affects appearance and how we present ourselves to the world. But not only that - if it is strong, the ascendant can come off as a complete alter-ego that mediates and changes planetary energy no matter how powerful, in the horoscope. Some people show off this tendency more intense than others. We could refer this as the ascendant personality type.
Imagine a disc pierced diametrically by an axle, making it easy to flip over no matter how heavy - this is how traits served on the plate that is the natal chart may be turned over and filtered by the ascendant irrespective of how strong the characteristics. Though pointed in a certain direction as determined by the positions of planets in signs and houses, a light wedge can alter the outcome significantly. We shouldn't view the ascendant as only of surface matter - moving as fast as it does, its position constitutes a unique viewpoint and important part of the self for every individual.
I have seen many examples over the years of a strong ascendant dominating over solar and lunar characteristics that were very potent in themselves. One was a solar and lunar Arian with Virgo rising. This person came off as quite shy and detached with a humble disposition. In retrospect, the mild and analytic Virgo ascendant personality only made the exhibitionistic, affirmation-craving and passionate Arian appear stronger as it eventually did turn up. The reserved Virgo actually made it easier for the Arian to gratify some impulses because of the careful, calculating manner of the ascendant. Another example involves a double Cancer woman (Sun and Moon in Cancer) with a Sagittarius ascendant. In this case, Sagittarius rising seemed at times to dominate completely over the highly charged emotionality and private nature of Cancer Sun/Moon. She was outspoken, witty and extrovert, with a tendency to brag (but also to be self-deprecating) and the typically blunt and tactless Sagittarian style was written all over her. This influence has remained. However, upon getting to know this person better, she showed an equally strong temperament of emotional turbulence and defensiveness. The Cancer-tendency to obsess over particulars and hang on to subtle hints and potentialities seemed to take over, but also make her more personable and sympathetic. In this example, the strong ascendant resulted in a pendulum between two very potent zodiac sign influences, whereas in the former example the strength of the ascendant more or less had the effect of creating a smoke screen for the quite fierce Arian underneath.
The simple answer is, hardly surprising, that there are no simple answers. Many (perhaps most) people cannot be classified as ascendant personalities since their rising sign never take the overhand on solar or other influences in any matter - the power of the ascendant has got to do with potential planets in the first house, sometimes conjunct the ascendant, strong aspects (especially squares and oppositions) to the ascendant and also the strength of the ruling planet and several other matters. Study astrology extensively - there is no other way.