Solomon's Key - Free, classic arcade remake
Solomon's Key was an arcade puzzle platformer game developed by Tecmo (now Koei-Tecmo) in 1986.
It was ported to several platforms including C64, ZX Spectrum, Amstrad CPC, Atari ST, NES and more.
You control Dana, a magician who is able to cast and destroy stone blocks, throw fireballs and avoid or destroy its enemies. The objective is to get a key which opens the door that advances you to the next level. Along the way there are several collectible items, some of them hidden under blocks and others appearing after casting and destroying a block. There are 51 levels including some bonus ones.
This is a free remake, staying as close as possible to the original.
Strategywiki has a full guide on how to play: