I have a question for example I buy a new hero for example Lord Weaver how much does it cost to upgrade him completely, so they medal to gold
Each of the paid heroes have a different total cost because the mall packs give different quantities of medals per pack tier purchase. Additionally, the cost can vary greatly depending on if you purchase only the least expensive pack multiple times over the course of several months or purchase as many packs as needed to get the hero to Legendary Grade in one day. You need 330 medals to fully max a hero.
Lore Weaver's mall packs give 10/15/25/40 medals. If you're looking for the most economical way to get her, you can purchase the least expensive pack 33 times or the two least expensive packs 14 times. To purchase enough Lore Weaver medals in one day you need to buy the first three packs and then buy most expensive pack 7 times.
If you're purchasing mall packs in US currency, Lore Weaver is a minimum of $165 and a maximum of $775. You'll need to do your own math for other currencies.