Venusblood EMPIRE: http://ninetail.tk/td08/VenusBlood-EMPIRE-_ch.html
Speed run: Emperor Difficulty, Advanced Mode. The combination of the two is the hardest in the game. This was done in 42 turns.
A few stupid mistakes were made, so this one might be able to be beaten in 35 turns?
Commander abilities are too overpowered. But without them, this game will be extremely hard to beat. Luckily, Venusblood HYPNO will address that.