I enjoy having the travelling merchant but he is missing a few items under the black codex option. These items include:
Rage Potion Bag
Shielding Potion Bag
Demonic Mobility Potion Bag
Holy Potion Bag
Onslaught Potion Bag
Demonic Ruin Potion Bag
Arcane Potion Bag
Potion of Annihilation Bag
These items are available on the codex vendors in all zones up to Southern Janost Forest. Some of these items are no longer relevant due to better options, but some are still viable such as the Arcane Potion Bag for mages. Please add the following three to the travelling merchant pet:
Arcane Potion Bag
Frenzy Potion Bag
Rage Potion Bag