All Levels
Missions - on a 3-10(up to 6-20 for high leveled players) minute cooldown but give a big chunk of exp and the primary way to get senryo.
Ancestral shrine - a shrine on the top right side of the map right of waterfall village. increase training speed(NOT MISSIONS) by 300%. lasts 20 minute on a 2 hour cooldown.
Bandits - Requires level 30 to 60. There are bandits around the villages. They are easy to kill but they only give 2 exp per kill. However, every 60 minutes you can get a "execution order" from a elite mission NPC. This increases the exp you get from killing bandits to 40 to 65 and after the execution order is over, you gain up to 10 senryo based on the amount of bandits you culled. Every bandit kill while on the execution order has a 1% chance to drop a "Bloodletter". The bloodletter increases experience gained from deer kills to 200 for 50 kills.
Samurais - essentially a tougher version of bandits. they will be in the top left corner(you know where the pylons are now). when you accept this contract (again, 5 minutes, 1 hour cooldown) you will get teleported there so sound villagers wont be fucked over by their distance. and by tough i mean a level 60 will have trouble fighting even one of them. they give 200-350 exp per kill and has a 1% chance of dropping a "Resurrection Seal", which decreases your death time by 25% as long as it's in your inventory. Droppable item.
Hidden Shrine - a shrine that appears once every half an hour in a random place. gives a "Charm of Glory" that grants 13000 experience to the user. Subsequent uses of the charm grants 1500 less experience down to a minimum of 4000 experience. Droppable item.
Elite Mission NPC - NPCs like Kakashi sell Secret Skill Scroll that increase the amount of experience you get from stat training by 10x for 2 minutes, essentially letting you train for 20 minutes worth in 2 minutes. This does not multiply with ancient shrine(you will get 13x bonus stacked, not 30x). This costs 5 senryo, then 10, then 20, then 40, and caps at 80. The cost of this drops by one tier every 2 hours however.