To survive Necron's Cross Slash at level 1, use a combination of luck and Auto-Life. You have a free Auto-Life you can learn, and then have Quina just cast Auto-Life so as to keep everyone alive. Use those powerful attacks (Thievery, Dragon Crest, Limit Glove). Necron only has 54,100 HP, so that means that you only need to perform six 9,999 attacks in order to win (actually five 9,999 attacks and one 4,105 attack). One thing you might want to do is not equip Jelly on a few of your party members. Necron can Petrify a character. But if you leave that character petrified, Necron might attack that petrified character, meaning that he just wasted a turn.