The Atari ST port of Shadow of the Beast was converted by Mark McCubbin and published by Psygnosis in 1990. While it’s not a bad conversion it does lack the graphical fidelity of the Amiga original and is also missing quite a few features.

The most obvious downgrade is that the scrolling is slower and jerkier than the Amiga version. There are fewer on-screen colours too.

The levels are structured the same as the Amiga original, but there do seem to be quite a few details missing (like the stalactites above the first bridge; the snails after the first boss, and other background graphics and enemies also seem to be missing).

That said: the Atari ST version of Shadow of the Beast still plays okay though. I enjoyed playing it, in spite of its shortcomings.

More: Shadow of the Beast on Wikipedia