This game is very beautiful and fun. I am puzzled why it has so few reviews and it hasn't become a classic.
The gameplay is very fun and also very various. Each level has something different to do so it never gets boring. There are many levels for a browser game. Six levels officially but each of them consists of multiple sub-levels so the game is pretty long and entertains for a long time.
The game is very humorous in a very kind and endearing way. The humor is not only in the cut scenes, but also in the very gameplay. The level where Caverman proves his love by jumping over stampeding animals and kissing his love is very funny just by how ridiculous it gets. I loved it when bigger and bigger beasts came and made me think: "Seriously? I have to jump over this? The last obstacle in that level was a bomb.
The art is very nicely done in this game. I love how story gets told trough comic like drawings that reveal the lighthearted struggles of Caverman in a very sympathetic way. The comic sequence how the man learns to stand upright by witnessing moon in a a puddle of water, lifts his gaze from ground to sky and is trying to reach the celestial body is both comical, touchingly beautiful and deeply symbolic at the same time.
Boss battles is something I always turn special attention to. I was very pleased about the end boss in this game. It's a very original idea to make the boss use a hostage. I have never played a (non-turn based RPG) game where player must fallow three life bars simultaneously - life bar of protagonist, life bar of boss and life bar of hostage. The boss fight was very original and fun. The difficulty could have been slightly higher but it was still decently tough.
From regular levels I liked the ocean crossing the most, the different obstacles and animals were great. But there were many other great levels, the jumping over stampede, the falling in volcano, the climbing on carefully balanced stone platforms - all are very good, original and diverse gameplay.
There are a few small nitpicks that hinder me from giving this game a perfect score, despite the many great moments. First I was not happy about the spear attack. It seemed strictly worse then the rock attack, which was too overpowered and the Caverman resembled a guy using automatic shotgun with the rapid and widespread attack of rocks. The time between shots should have been bigger and somehow each attack should have it's own strength and weakness. I think rocks should do far less damage then the spear, but they could make up for it with their spread. Second problem was that in some levels, especially the first ones Caverman died if he crossed the edge of level, this shouldn't happen, the edge should act as a wall instead like it is in most games.
I have played commercial games on prehistoric theme using the same type of flintstoney humor, games like Prehistoric, Prehistoric 2 and Prehistoric Man and I must say I like this humble browser game better then them. This is more then a game it is also a piece of art and I am getting the feeling that many of Munguia's games are like that.