Today's update added chapter 6 to the game, which is the last one listed on the Japanese wiki. And with chapter 6, it offers the endgame grind, rather than relying purely on whichever event is active.

Maps 6-1 and 6-2 are along the lines of what you'd expect so far. Map 6-1 is actually easier than the chapter 5 alternate history map, though 6-2 is perhaps a little harder than it.

As I reckon it, the PVE endgame starts in chapter 6-3. For starters, normal, repeatable campaign opponents that you can fight 50 times per day have a chance to drop gold tickets, rather than only the copper tickets on previous maps. Starting with the seventh opponent on the map, you also have a chance at curse fragments. You know those items that have been available for trade at the port requiring curse fragments? It's possible to get them now. The opponents in 6-3 that can drop curse fragments actually have you fight nine generals at a time, not five.

At the moment, Temp and I are the only ones who have beaten a map that drops curse fragments. I expect a few others will do so pretty soon as they get on today or whenever they decide that they want to clear chapter 6. To be strong enough to win that map is, at least for now, to be strong enough to be a contender to win the Daimyo tournament.

If you clear 6-3 and move on to 6-4, it's back to more normal opponents for a while, with five generals on a side again. At least, if you regard opponents with about 35000 attack, 18000 defense, 22000 troops, and 170 speed per general as "normal". But these opponents have a chance of dropping two gold tickets, not just one. Furthermore, starting with the fourth opponent on the map, they have a chance of dropping curse fragments. Even the worst victory outcome of some copper still gets you 7k-10k, which is up markedly from earlier maps.

Temp and I both got stuck on the same spot: the eighth opponent on map 6-4. Or at least I assume Temp attempted it and failed rather than just arbitrarily deciding to stop. No one has beaten that map yet. It's a huge jump in difficulty over anything that comes before it, so I expect it to be a while before it gets cleared. The five generals are elite marksmen with 42342 attack, 29792 defense, 246 speed, and 25890 troops each.

I haven't yet gotten any curse fragments to drop, though I did get a 2 gold ticket drop from beating a map in 6-4. That's a small sample size (8 wins on 6-4), so it really doesn't tell you very much about the odds.

For what it's worth, in the summer generals event, the SSR EVO card had a drop chance of about 0.2%, as I had 12 drop out of 5600 chances, which is a large enough sample size to get a decent approximation. So DMM is willing to set the drop rates for things that drop from clearing a map that low at least sometimes. The SSR generals that drop from some early hidden dungeons also have drop rates in that ballpark.