Herdy Gerdy was one of the first games I had on the PS2. Looking back on it now, it gets many things right, such as its design, and many things wrong, such as its engine and camera.
The visuals were beautiful, lush and colourful. The levels seemed quite large and open, and there was plenty of detail in the environments. The sound design was brilliant to, with a memorable soundtrack, good environmental sounds all of which are backed up by the chirping of the creatures in the areas. The attention to detail in character animation at the time was quite good as well. The games visuals and audio are full of personality.
The gameplay is a similar to many open platformers at the time. Herdy Gerdy was one of the first games to properly do Mario 64-Like worlds and levels. Roaming the levels, finding collectibles and herding creatures is the order of the game, and although it doesn't sound very exciting in writing, the game plays very well, minus some occasional drop in framerate, and sometimes uncooperative camera in tight spaces. On top of this, the AI is really stupid, and I mean suicide stupid, which can prevent you from getting 100% until you restart the level or come back later because of how stupid they are.
The game, if you play through it slowly, or try to find all the collectibles will take you much longer than any modern AAA game, and if you just run through the levels as fast as possible, the game will still take as long as most modern console games, even though the game has skippable cutscenes and no Quick-Time events.
Overall, this is under-appreciated, and a relic of bygone age when games tried to innovate, come up with new ideas, and try to develop gameplay, not trying to pull "cinematic" wool over gamers eyes. Its a shame that the game was overlooked, because it has as much charm and content as some of the best games of this console generation, and it deserves better than to be left to be forgotten, despite its niggles.