Complex sentence: He has been a portrait artist for twenty years, but later moved into life painting, combining non-traditional techniques, including dripping paints, splats and blobs of paint, scraping, scratching as well as more conventional painting methods into a complex layering process.
Split into simpler sentences: He has been a portrait artist for twenty years, but recently he have moved into the more traditional genre of life painting, however the techniques and methods used are far from traditional. He combines techniques such as dripping paints, splats and blobs of paint, scraping, scratching as well as more conventional painting methods into a complex layering process.