Let's see... The bad guy that is consistent between the two is the dark genie (hence dark cloud)
In the first one. the dark genie is awakened and he has extreme evil powers. and he goes around destroying the world. But the good fairy. (he's an old man, kinda looks like a priest) traps everyone and there stuff in bubbles. and you as the hero who was also saved my fairy man must go on a quest to restore these bubbles and reset up the towns. So you go into dungeons that have been plagued with evil and fight your way to save the bubbles that have been scattered. (all the fairy man could do was save everyone, not stop the bubbles from getting scattered) than you reset up the town. and you can set it up almost any way you want. including setting up roads, and rivers, and trees.

One of my favorite parts is that it isn't a turn based fighting game. you can run around swing your weapon. upgrade it in unique ways. Block, jump backwards to avoid hits. its a very cool game.

And the second one has similar things that happened. BUT you're an inventor, so you can take pictures to get "ideas" and you can than use the ideas to invent new things. and along the way in both games you can get to characters to play with to solve different puzzles.

and just ... so awesome <3