I am at 10/25 of the blue portal and the snow dragon HP is 608k. I have enough strength and enough HP to outlast it but I ran into the problem that you only get 10 rounds to kill the monster before you are automatically killed. The best I have got is to get it down to 48k HP after my 10th turn. I hope they remove the 10 turn limit as it's pretty frustrating. Also even if I get past this one I doubt I'd have a chance on 11/25, I don't know what that HP is going to be but it's been making huge leaps in the last few rounds.