When I buy ophion it tells me to save the transaction id. Is there a reason behind it like it's not manual and we have to contact you with that transaction id?
No reason, Its just worth logging it yourself in case you have issues and you can refer to the transaction you had issues with.
The mnemonic passphrase however is your only way back into your account should you lose your password, This is also a reason we did not allow automated password resets, We wanted this site as secure as possible.
Keep that safe.
So, in essence, you can log back in to your account with the mnemonic seed only if you needed too, but also write down your private keys and such just in case?
Also, it seems privacy is a big concern here... Can anyone run nodes to ensure decentralization? Also, what do we do with ophion coins exactly? Do we only purchase stuff on the market place with those coins, or maybe can we use that and bitcoin/other altcoins as well? I'd personally like to use monero for the extra privacy on top of TOR.