With a name like that, it doesn't seem wise to click this link. Regardless, this page details all of the activities that Chaos has done (or tried to do) in more or less chronological order.
A single member of Chaos acting alone convinced a Celebi to bring him back in time 25 years. He messed with a couple key events.
First off, he killed Destiny soon after she was born. She was originally going to become the Fate of Jim, Rated, and several other important people. She was a much more responsible Fate than Nicole turned out to be.
Second, he stopped Nicole from dying. Originally, she ran into a building that was on fire to save her brother (Xavier). Xavier went on to be a powerful force for good. Now, Nicole is alive and became a Fate in Destiny's place. She was very bitter about not being able to save her brother, so when she got control over many people's lives, she decided to have some fun. Trying to ignore the past, she messed with people while ignoring the consequences.
The only ones who still remember how things were before Chaos went back in time are the member of Chaos himself and Holly, who has the powers of Dialga.
One of Chaos's main goals is to kill Fates.
Alex - He was attacked four times by Chaos. The first time was at Stark Mountain, followed by route 229, then SS Rho, and finally the Ice Path.
Chaos hasn't made any other (known) assassination attempts recently.
Another one of Chaos's main goals is to cause worldwide disasters.
Chaos captured Articuno, Zapdos, and Moltres so they could make them fight. If they were to fight, they would cause worldwide disasters. However, Lugia would stop them. So, they also captured Lugia. They tried to capture Ho-Oh but were unsuccessful. They released all of the birds except for Lugia. Groudon and Kyogre (Justin and Rated) used their weather based powers to keep things from getting out of hand while others (Jim, Molly, Christine, and Jessica) found and released Lugia. Lugia managed to calm down the other legendary birds.
Choas has made no other attempts to destroy the world at this point.