A wonderful example of a tie-in game. It was a blast to play almost 30 years ago and it still holds up today. The art of the game resembles that of a movie and the soundtrack also fits the level themes with the already familiar motifs from the said movie. The gameplay itself is simple - jump on platforms, jump on enemies and slap the enemies in the second half of the game. Combined with a good level design, that uses not only horizontal progression, but also goes vertical - it delivers a satisfying experience.
Unfortunately the game still has its drawbacks. For example the roar is rarely used as a mechanic and can be easily ignored. Also there are certain traps that you need to be aware of to pass them - otherwise you'll lose a life. Basically a certain death for a first-timer. And there are a couple of unnecessary tedious parts: monkey puzzle, the cave maze and the last Scar part. And if you can brute-force through the first two - the last one requires the knowledge of a specific move to execute. Being the very last bit of the game - it can taint the whole experience.
So yeah. This is a wonderful game, but like many games of that era it requires repetition: do a few steps, fail on one part of the game, learn that part of the game, repeat it, do a few more steps. Too bad there is no in-game solution on how to teach the very last part. Not sure about the difficulty though. Maybe it's muscle memory, maybe because it was PAL version, but I had no problem completing the game first try after many years. And back when I was 5 I was still able to beat it, and getting past level 2 wasn't such a problem.