To trigger the most difficult (and most lucrative) path for this week, you must bring a spear unit level 80+ There is no speed/turn requirement this week If you bring a 80+ spear unit, then on the second floor a unit will appear near the top that says "I hate spears..." Kill this unit or else it flees. The boss is ice element and is a bit stronger than previous bosses. For first turn he will send a message "Beware X" where X is a quadrant of the battlefield, like upper left or lower right. The boss is going to move to that area and cast an area 2 ice spell that can kill most characters (a few z-class are strong enough to weather it). After that the boss will cast a lateral ice attack each turn and then occasionally project a new quadrant that he will hit with his more powerful area attack. There is an HP threshold (somewhere around 20-25%) where he will cast blizzard, dealing heavy ice damage to your team. Initially I was setting up triple pincer on the boss but this ended poorly for me as I couldn't outright kill boss and then he wiped out some characters with icicle attack and then the rest (if I couldn't kill second turn) with blizzard. Things are much easier now by setting up IN THE MIDDLE AREA so as to dodge his initial icicle attack, and then work him down more steadily until a burst finish when he's closer to his low HP threshold. Also note that the smaller accompanying dragon thing casts icebind area 1. Rewards include yukken or maverick otomos. For Nia recode, boss and luck chests may give white essence. Rascal drops from higher luck chests (I've seen in 80 chest), I don't know about negotiator in the encounter. My 100 luck team is seiryu equipped with zack, Shin'en with staff of Apollo, camellia^ with skullsplitter, lich^ with wwwand, bahamut^ with z dragon, suoh^ with rune. What else is important to know?