Beersaurus is (as the name suggests) a dinosaur themed beer bar in Ikebukuro. They have approximately 4 American craft beers on tap (too bad if you don’t like IPA) and a huge selection of bottled beer. Normally, this place is damn expensive (1,260yen/pint) but during happy hour from 6pm to 7:30pm tap beers are half price. 630yen for the likes of Green Flash, Ballast Point, Lagunitas and Bear Republic is a pretty good deal.
Beersaurus is on the 3rd floor of a corner building on a major intersection.