I think it's more than possible to do, but you may have to be more specific. It narrows it down a lot, but a 'creature raising system' is still pretty vague, in my opinion.
You might want to specifically tell us what you are looking to emulate in terms of a feature list, such as creature stats, some sort of transformation/growth system (like, I mean Pokemon, Digimon, etc, if you catch my drift)
Creatures stats,
Items to be given to the creatures to upgrade those stats
& an evolution system for when the creature reaches those certain stats.