For Magic's Guildpact set, Liam Sharp illustrated the Gruul Scrapper, Scab-Clan Mauler, and Skarrgan Pit-Skulk cards for Wizards of the Coast.
The Magic: the Gathering cards illustrated by Liam can be viewed here: http://gatherer.wizards.com/Pages/Search/Default.aspx?action=advanced&special=true&artist=+[%22Liam%20Sharp%22] Note that the gatherer database does not usually show promotional cards. The gatherer can also experience difficulties with links like this. If you are taken to an error page, click on "advanced search" at the top of the screen. Once on the advanced search page, scroll down to the artist search bar, input "Liam Sharp", then click "Add," and go back to the top of the page to click "Search." You should arrive at the page linked above.