To get the best rewards, including upgrade materials and in-game currency, you will want to get all the collectibles. Here are all HIA Commemorative Coin collectible locations in Zenless Zone Zero.
This list is a WIP and will be updated as soon as possible!
Where to find all HIA Commemorative Coins in ZZZ
In order to find all H.I.A Commemorative Coins in ZZZ, you have to talk to passersby. You have to check during all times of the day (and night) in order to get all of them.
You can exchange these Coins for valuable items and Dennies with the Sage in the Barrel, a trash can at the end of the street near the 141 Store. You will also get a medal when you collect half of the coins in a single area; just talk to Officer Mewmew located right outside Howl's News Stand.
The fastest way to check whether you can collect any coins at the moment is to click up top on the time of day. If the text tells you that Sage wants more coins, that means you can find someone that will give you a H.I.A Coin.
Don't worry, you don't have to go around talking to everyone. The people that have Coins will have a gray speech bubble over their heads. Sometimes all you have to do is talk to them, and sometimes you'll have to do something quick or pay them. It usually takes only a minute or two, which isn't a waste of time considering the great rewards.
When it comes to items with Coins, they will have a shiny effect around them, so you know to check out the item.
All Sixth Street HIA Commemorative Coin locations in Zenless Zone Zero
Morning
#1 Ellis
In order to start your collection, you will first have to talk to Ellis at the Noodle shop who will have you investigate the trash can at the end of the street. Ellis will also give you your first H.I.A. Commemorative Coin.
#2 Mrs. Yani
You can find Mrs. Yani next to the street sign across the street from the Remodeling shop. You will have to go check if 141 Shop accepts the HIA Coin. Once you tell Mrs. Yani that they don't, she will give it to you.
#3 Sjal
You can find Sjal handing out flYers in front of the Noodle shop in the morning. She will just give you the coin.
#4 Plants
Afternoon
#5 Travis
Travis will be right outside the video store, so he isn't hard to miss. Talk to him to get the HIA Commemorative Coin.
#6 Clara
You'll find Clara standing in front of the street sign across from the Remodeling shop. She will ask you to take a photo of her. Once you do, she will give you the HIA Coin.
#7 Lupita
You can find and talk to Lupita across the street from the 141 store during the afternoon.
#8 Panda
The panda toy will be sitting at the coffee shop drinking a beverage. Apart from the fact that it's extremely cute, checking it out will give you a HIA Coin.
#9 Record Box
You'll be able to loot the left record box in front of the Bardic Needle store in the afternoon for an HIA Coin.
Evening
#10 Jonah
You'll find Jonnah in front of the Godfinger arcade. He will trade you for Godfinger tokens which you will have to give to him once you see him in the arcade.
#11 Roy
Roy will be standing in front of the 141 store, so you can ask him for the Coin. He will ask for 300 Dennies for it, so be sure to have some (though that isn't terribly difficult).
#12 Locker
After you've collected a few Coins, check the locker next to the workbench at the shop during the evening.
#13 Dumpster
You will have to go dumpster diving in the evening for one HIA Commemoration Coin. This is the dumpster right behind Officer Mewmew.
#14 Luo
Next to the Turbo Remodeling store where he is talking to Phil. He will say he dropped the coin somewhere. Climb up the stairs to the left and onto the roof of the Remodeling store. You'll find the coin in the empty crate.
Midnight
#15 Gerant
You'll find Gerant next to the road block. He is too scared to walk on his own, so you have to go find his colleague Sita located right behind the newsstand. She will give you two HIA Coins to take to Gerant to ward off the ghosts and for good luck. He will give you one so you also have protection.
#16 Skateboard Bench
Go to the Skateboard bench next to the Boxgalaxy store when it's Midnight. Search it to find the HIA Commemorative Coin.
All Brant Street HIA Commemorative Coin locations in Zenless Zone Zero
Morning
#17 Kaede
She can be found right next to the elevators. You need to ask Cole a question about how he calms himself before going to the Hollow and go back to tell her. She will give you the HIA Coin afterward.
#18 Becky
Becky is standing next to to the Junction box. She will give you a coin as soon as she finishes telling you about the Vending Machine perfectionist that refuses to take wrinkled notes.
#19 Luka
You don't have to go far to find him, since Luka will be next to Becky near the Junction box. H will give it to you in exchange for some Dennies (your choice how many you want to give him).
#20 Ronnie
Ronnie is standing near a bunch of crates in the middle area. She asks you to take a photo of Kousaka before she gives you the HIA coin.
Afternoon
#21 Gray
Gray can be found next to the orange and blue truck. He is making 'music' with pipes. All you have to do is chat with him for a bit before he gives you the HIA Commemorative coin.
#22 Ironhead
He is next to the stack of cement bags stressing out about someone making counterfeit money. However, it is just an HIA Commemorative Coin which Ironhead found, and he will give you once you explain what it is.
Evening
#23 Jen
Jen will be standing next to some crates in the middle area. You have to talk to Kaishu to give him his items that Jen found, and he will give you the HIA Commemorative Coin.
#24 Li
Talk to Li and then examine the cement bag in front of him for a HIA Commemorative Coin. Once you check it, tell Li that he didn't break anything to give you the coin.
#25 Yang
Talk to Yang next to the pipes, who will tell you there is a Builderboo stuck in the pipes. Talk to it first, then go back to talk to Yang, and the Sulking Builderboo will give you the HIA Coin.
If you want to improve your agents, check out How to unlock material farming in Zenless Zone Zero on Pro Game Guides.
