Considering they're the compressed remains of dead animals and plants, it's amazing how important fossils are. And we're not talking about the museum attractions that were once Tricerotops and Diplodocii either. No, billions of tons of crushed rainforest are what make our trains, planes and automobiles run, not to mention providing us with electricity. Without fossils – and fossil fuels like oil and coal – we'd probably still be living in caves.

Happily, we don't have to chip away at rocks with a little hammer everytime we need to drive down to town. Civilisation's good like that. It sorts out most of the boring stuff for you.

It's a lesson the makers of Pokémon-esque fossil-collection and creature evolving and battling game Spectrobes seem to have only half understood. Which is a shame, not just because we had such high hopes for the game, but because it would only require a bit of fine-tuning to replace some of that drudgery with enjoyment.

But first, down to business. You're Rallen, a young Planetary Patrol officer, who's been chosen to unleash the power of these fossilised creatures against an invading wave of critters known as the Krawl. And so before too long, you're wandering around a mysterious planet with a baby spectrobe in tow, searching for fossils.

Considering there are around 80 basic types of spectrobes to collect (the '500' figure Disney has quoted includes all minor variations), you have to accept you're going to spend a lot of time poking the ground with your stylus. Once you've found a fossil, you drill around it with the stylus, selecting different-sized drills as you delve, until you've uncovered the fossil sufficiently to pick it up. Mess up with the drill though and you'll destroy the fossil.

While excavation was never going to be the most fun part of this game, what's more annoying is you eventually discover the activity isn't all that useful. Firstly, you're soon finding the same type of fossil over and over again, which means you stop digging them up. How many of the same spectrobe can anyone need?

Actually, that's not a stupid question. When you get further into the game, you can customise your spectrobes with extra bits to vary them. Which brings to light the second problem – there's no real advantage to seeking out more than a dozen or so spectrobes. Like Noah, you don't need more than a couple of each type.

The unfulfilling nature of fossil excavation is a real missed opportunity. As well as being hugely ambitious, Spectrobes is enormous. Front-loading the opening couple of hours with some more easy-to-grab spectrobes wouldn't have had much detrimental impact on a game with so many other extras.

As well as digging up spectrobes, other items you'll find underground are minerals, which are required to evolve the spectrobes from their baby form into their adult, fighting form. Also hidden away are the information cubes needed to open up various game features, such as the Nintendo Wi-Fi Connection and ability to use the four creature cards included with each game to unlock more spectrobes.

Aside from digging, battles are what take up the rest of your time. Thankfully they're much more fun.

Battles are triggered whenever you come into contact with the dark Krawl forces that move around the environments you're exploring. You can outrun them if you want to, but as battles are how you level up your spectrobes and get cash, usually it's best to get stuck in.

As with the Pokémon games, battles take place in a special battle area, although unlike Pokémon, the action occurs in real-time.

You fight simultaneously, with one adult spectrobe positioned either side of you. They'll follow wherever you move and you get them to attack using the left and right shoulder buttons. Pressing a shoulder button will either unleash that spectrobe's default attack or, with some types, open up another menu with more command options. Alternatively, once you've built up your energy meter you can press both buttons to trigger powerful combo attacks.

It's a system that works well, even if compared to Pokémon, the battles in Spectrobes aren't anything like as mentally stimulating. Partly that's an issue of it being real-time; the key skill is spatial co-ordination, rather than choosing the right creature or attack.

As you play further into the game, this tactical deficiency becomes more apparent. There's little reason to use the full range of your menagerie, especially as the two spectrobes you fight with the most will quickly level up to a much higher stage than the others. There is a paper-scissor-stones mechanic in place (see PG Tips below) but to be honest you can disregard it provided you've sufficiently powered-up your core spectrobes.

It's this sort of minor but undeniable disappointment that sullies many of Spectrobes' features. If only there was a larger variety of fossils earlier in the game, or if the evolution process happened faster, or if the game wasn't quite so complicated, things would be different, and better.

This isn't to say Spectrobes is a dull game, only that it's not quite as exciting as we'd hoped it would be. Buy it and you'll enjoy it, especially if you get heavily into the online options where you can swap spectrobes and their various custom parts, upload your scores, download movies, and battle head-to-head against other Spectrobes masters. But compared to Pokémons Diamond and Pearl, we have to admit that for all its DS innovations, Spectrobes is a bit of a fossil.