<p>Current answer: As of the release of the <a rel="nofollow" href="https://tibia.fandom.com/wiki/Updates/12.40">Summer Update 2020</a>, the creatures that gives most experience are the <a rel="nofollow" href="https://tibia.fandom.com/wiki/Infernal_Demon">Infernal Demon</a> and <a rel="nofollow" href="https://tibia.fandom.com/wiki/Bony_Sea_Devil">Bony Sea Devil</a>, which yields 32500 experience points each. The creature that yields less experience are still the same: Penguins and "fake" Phantasms (1 exp). </p><p><img alt="" src="https://tibia.fandom.com/wiki/Special:Filepath?file=Infernal Demon.gif" style="height:64px; width:64px"><img alt="" src="https://tibia.fandom.com/wiki/Special:Filepath?file=Bony Sea Devil.gif"></p><p>Original answer: Currently, the non-boss creature that yields most experience is the Brain Squid, which yields 19,635 experience points. The creatures that yield the less experience are Penguins and the "fake" Phantasms which yield 1 experience point.point.</p>