Delivering the online course content to learners in better ways is the most important thing in educational ecosystem. Course creators should combine different components from different sources to provide qualitative and useful course content. XBlock is a powerful tool that allows enhancing and extending the Open edX platform to meet learners and teachers future needs, and is a great way to create interesting and attractive courses. XBlock usage allows combining different formats like text, audio, video and other multimedia objects into one course and offers an APIs for other modules in the edX to communicate with the course content. Xblocks provide the convenient interface for delivering various training materials to the learners. Raccoon Gang provide full spectrum of custom Open edX development which includes XBlocks development, as well. We have a great experience in building and supervising in such courseware components including edX video player, edX video pre-rolls, chemical equation problem, conditional, poll, LTI, drag&drop, Shindig, etc.