There's a simple way to beat the last level.
1) Get all of the left hand free jellies activated.
2) Fill the jelly in the top left corner by daisy chaining the jellies on the left side (this avoids most forts).
3) Once the pirate has upgraded the top lab, start dumping all of your jellies into it. Get as many as you can in that lab. He'll fight you, but will eventually give up. If the pirate activates green or red on your lab or top left jelly, just restart.
4) Eventually the pirate will get low trying to fill everything. When it gets low, dump your lab into the pirate jelly to take it. Leave yourself some wiggle room since the pirate fills quickly. Since lab jellies travel fast, they can bypass forts without taking many hits. You will probably lose all your other jellies during this process.
5) Once you have the large jelly, let it fill up then send jellies to the labs. Use the labs to take all of the forts Now you can use the pirate to overtake everything else.
I have to give it 2/5. This game had a lot of promise. It could've done as well as Sacred Seasons 2, but it failed on too many levels. The inventory is too limited. Contract items take up space. They're quest items and you should be able to at least remove the items that have been completed. Pets also take up space along with masks and such. It's almost impossible to join a guild since you can't tell which ones are actually active. You spend days and days sending requests and never getting an accept or decline. The rewards offered for revisiting levels doesn't seem worth it. Essentially you'll have to complete the revisit with better equipment than you're rewarded. For example, you need a character level of 15 and level 12 equipment to complete particular a revisit, but only offered a level 6 reward. Then you're only offered 20 or 40 coins to sell that reward. It's just not worth it. This game had a lot of potential and I'm kind of sad/mad it didn't deliver.
For all of those who are having problems with the game not loading and only getting a black screen, make sure the "Allow third party Flash content to store data on your computer" option. Right click the game and select global settings to find the option. It worked for me.