Wide-field optical imaging is fundamental to nearly every area of astronomy and astrophysics at all wavelengths, particles, and gravitational waves and are the highest demand instruments on their respective telescopes. We have entered the era of billion-dollar 'mega-facilities', such as the James Webb, Roman, and Euclid Space Telescopes, the Cherenkov Telescope Array, the ESO ELT, Giant Magellan Telescope, and Thirty Meter Telescope, the Square Kilometre Array, KM3Net, LIGO/Virgo/KAGRA and future gravitational wave detectors, among others. These facilities require deep, 8m-class wide-field optical imaging to help achieve their main science objectives, obtain deep, accurate photometric redshifts, localise sources and identify and study their host galaxies, and answer long-standing questions. However, existing 8m-class wide-field imagers do not have several much-needed wide-field optical capabilities, and no such imagers are planned on Earth or in space for the next 2+ decades. These capabilities include very deep (m ~ 28-30) u-band and 3000A-10000A imaging, CMOS fast imaging, broad, medium, and narrow band imaging, low surface brightness capability, fast filter change (~10s) and fast (~10s) readout, rapid-response capability, and real-time data processing and source identification for minutes later spectroscopic capability. I will discuss a UV-sensitive optical wide-field imager for the GTC, unique and leading-edge science it will do, and why it will keep GTC a leader in the ELT era.