You can't unequip items and have nothing equipped. In order to unequip an item, you must equip a second item. You can't craft things with items that are equipped, so if you equipped anything but the highest tier item, you'll a backup copy of the lowest tier item for that slot if you want to progress.
It's Oryx 16-bit Fantasy Sprite Set. You can find it here: http://oryxdesignlab.com/sprites/
Also check out Dungeons of Fayte and Realm of the Mad God for two awesome games with these sprites :)
I would recommend learning physics before attempting to teach physics. Specifically, I would recommend a course in Optics as well as an introduction to Quantum Mechanics in order to acquire the knowledge that would have been necessary in order to make this game well. A case-by-case correction list can only accomplish so much; an understanding of the material is needed in order for the holistic product not to cause pain to people who do know the material.
@lakawak I have no idea what you are talking about. This game appears to be a fairly awful one-button running game. I see no enemies or bookshelves, let alone money. Whatever game you were critiquing sounds interesting, but it is not this one.
Sometimes levels (particularly the swamps) spawn with no method of victory. After obtaining the quest objective there is still no down staircase anywhere on the map, and using the up staircase results in 'defeat'. Maybe I'm missing something
I'm pretty sure this is copyright infringement, which is not tolerated under Kong TOS. Character and concepts used without permission from other sources can be done legally and within the TOS but only in certain limited cases which I feel like this falls outside of; it certainly isn't fair use under US law.
Things that don't work that maybe should: bazaar, complex, jungle, xenodochium, smithy, refinery, nuclear power plant, bomb shelter, bunker, saloon, manor, foundry, music studio, haunted house, dance hall, longhouse, fixer upper.
Also, the game does not end automatically, even when all spaces are filled. Fun game though.
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working on unequip :)