Complex sentence: In July of 1998, the company launched this web-based offering as "Excite Games by TEN" and built a large audience by offering co-branded browser-based games to many of the portals available in 1998.
Split into simpler sentences: In July of 1998, TEN launched as "Excite Games by TEN". TEN built a large audience by offering co-branded browser-based games to many of the portals available in 1998.