Tetsu's trades starts with Tetsu in Ninja - Gunslinger map (22, 62). The steps below are read from the quest's script on this server, in the order the script's quest stage moves through them.
Walkthrough

1 Talk to Tetsu in Ninja - Gunslinger map (22, 62)
When Base class is Ninja Choose “Fuuma Shuriken Beneki” then “Yes! Make it for me!” Have with you 50 ×
Steel, 20 ×
Harpy Feather, 5 ×
Oridecon, 90,000 zenyIt takes 50 ×
Steel, 20 ×
Harpy Feather, 5 ×
Oridecon, 90,000 zenyYou get 1 ×
Huuma Wing ShurikenIn order to make the Fuuma Beneki, I need
50 Steel, 20 Harpy Feather
5 Oridecon, and 90,000 Zeny.
Do you want me to create this item for you?
Script:
npc/quests/ninja_quests.txt:1193
2 Talk to Tetsu in Ninja - Gunslinger map (22, 62)
When Base class is Ninja Choose “Fuuma Shuriken Daisharin” then “Yes! Make it for me!” Have with you 30 ×
Steel, 100 ×
Tassel, 2 ×
Oridecon, 40,000 zenyIt takes 30 ×
Steel, 100 ×
Tassel, 2 ×
Oridecon, 40,000 zenyYou get 1 ×
Huuma Giant Wheel Shuriken [3]Fuuma Shuriken Daisharin In order to create Fuuma Shuriken Daisharin, I require...
30 Steel, 100 Tassels
2 Oridecons, and 40,000 Zeny.
Do you want me to create this item for you?
Script:
npc/quests/ninja_quests.txt:1241
3 Talk to Tetsu in Ninja - Gunslinger map (22, 62)
When Base class is Ninja Choose “Fuuma Shuriken Daisharin[4]” then “Yes! Make it for me!” Have with you 20 ×
Cracked Diamond, 1 ×
Huuma Giant Wheel Shuriken [3], 3 ×
Oridecon, 40,000 zenyIt takes 20 ×
Cracked Diamond, 3 ×
Oridecon, 40,000 zeny, 1 ×
Huuma Giant Wheel Shuriken [3]You get 1 ×
Huuma Giant Wheel Shuriken [4]Do you want me to create this item for you?
And in case you don't know...
In the process of slotting a weapon, your weapon will lose any refine points and slotted cards, if any.
Think this over with caution, and then decide if you really want to do this or not.
Script:
npc/quests/ninja_quests.txt:1294
4 Talk to Tetsu in Ninja - Gunslinger map (22, 62)
When Base class is Ninja Choose “Fuuma Shuriken Rekka” then “Yes! Make it for me!” Have with you 50 ×
Steel, 100 ×
Live Coal, 100 ×
Burning Heart, 50 ×
Flame Stone, 78,000 zenyIt takes 50 ×
Steel, 100 ×
Live Coal, 100 ×
Burning Heart, 50 ×
Flame Stone, 78,000 zenyYou get 1 ×
Huuma Blaze Shuriken50 Steel, 100 Live Coal
100 Burning Hearts, 50 Burning Stones
and 78,000 Zeny.
Do you want me to create this item for you?
Script:
npc/quests/ninja_quests.txt:1341
Rewards over the whole quest
1 ×
Huuma Wing Shuriken; 1 ×
Huuma Giant Wheel Shuriken [3]; 1 ×
Huuma Giant Wheel Shuriken [4]; 1 ×
Huuma Blaze Shuriken
How this page is made: every step comes from the NPC scripts the server loads for Episode 13.2 (the file and line are under each step). "When" lists the checks the script makes before that branch runs; "Have with you" are the items it counts; experience from getexp is multiplied by the server's 50x quest rate. NPC lines are the script's own text.