Remember, although samurai has bonuses against unique units. They are still very strong against generic units due to fast artack speed. It's generally a good idea to kill them with archers, since they have lopierce armor.
Using Skirmishers behind your Obuchs, you could trade effectively versus Samurai. Pretty impressive considering their attack bonus vs the Obuchs. Chipping away that pierce armor turns your skirmishers into archers
Remember, although samurai has bonuses against unique units. They are still very strong against generic units due to fast artack speed. It's generally a good idea to kill them with archers, since they have lopierce armor.
samurai: Armor shredding? how interesting but no match against my sword!
*Walks off and gets killed by a Skirmisher*
Using Skirmishers behind your Obuchs, you could trade effectively versus Samurai. Pretty impressive considering their attack bonus vs the Obuchs.
Chipping away that pierce armor turns your skirmishers into archers