How do you beat kaos.And play more levels after you beat Laos?

I just finished and it took me 28 skylanders to beat Kaos. This was my first attempt so I will probably improve.

You can NOT actually KILL Kaos.
Once you have completed Lair of Kaos, the game will take you to Kaos' castle. There are no treasures or scrolls or gems to collect in Kaos' castle. You just have to FIGHT a WHOLE BUNCH o Kaos' horde of Minions. That fight takes a LONG LONG time. I own 30 of the skylanders, plus all the legendary. I even own Dark Spyro, which means I have 3 spyro's in my arsenal. ALL of them have been leveled up to 10 and all but 2 have purchased ALL the upgrades from persephony. The final upgrade can't be purchased until you collect the soul gem in lair of kaos for Double Trouble.

Even with that HUGE arsenal of good guys, it took me nearly an hour to fight and defeat wave after wave of Kaos' minions sent against me. Repeated Sharkwave of Doom attacks, laser attacks, those green balls, and of course MORE waves of Minions. Unlike the lower levels where you are finished when you have defeated ONE group of three, in the final battle, there will be wave after wave FREQUENTLY at the same time as shark attacks. The very last one hits you with EVERYTHING at once. 3 minions PLUS all three of the other evil spells. I lost count of how many waves there were after 10 or 15 minutes. I didn't think it would ever end.

I think Kaos used his entire arsenal. I managed to DODGE and fight long enought that eventually the HYDRA ran out of energy.

I tried shooting Kaos and his Hydra, with everything in my arsenal. I got a LOT of direct hits, which I believe weakened the hydra a little.

The main thing is: to defeat Kaos, you must somehow manage to survive all the attacks. EVENTUALLY the hydra will run out of energy and you will win. The trick is to have as many skylanders as necessary to KEEP replacing your exhausted ones, so you can keep fighting.

Unfortunately, there are NO levels after Kaos, Except for the FOUR adventure packs which you can purchase.

Once you defeat Kaos, your options are
(1) Complete the Heroic Challenges.
(2) Reset the game and play again using different skylanders to make it interesting.
(3) Go back and complete any levels where you do NOT have all the check boxes in Objectives. The Enemy Goal one requires that you kill EVERY enemy on the level. That can be tough because some are hard to find.
(4) You can also redo the levels using your FASTEST skylander. If you do not stop to gather any treasure, money, gems, etc. AND you do not kill any enemies that are not absolutely necesssary. AND you do NOT go throw any of the elemental gates, AND you do not make ANY mistakes, You just MIGHT be able to finish the level in UNDER the "Time target".

If you can successfully gather EVERYTHING to be collected, Get ALL the objectives, complete all the Heroic Challenges. THen you WILL HAVE accomplished something major.

If you want one last challenge. Take ONE skylander and complete ALL the heroic challenges, Take the SAME skylander, and start a NEW game. Leave the skylander leveled up and with all his upgrades. NOW try to complete the ENTER set of all the chapters using that once skylander, without getting killed. Talk about a CHALLENGE!!!