Practice fee
Also called: taker fee
The 0.40% fee Aureus charges on practice crypto trades, modeled on real exchange rates.
In practice
It's charged to your practice cash as its own labeled line, so you can see exactly what the friction costs. Entry-level taker fees at major US exchanges run 0.4–0.6%.
What it is not
Not real money and not revenue — it exists so practice results don't flatter you by pretending trading is free.