Experience - Just hard work & Time and or Rubies
Gold - We worked out that the scrolls can assist with probably 5 million every 2nd Days [When Maxed out] - Who Knows - probably more depending on the number of high value scrolls
Gear - Forging consisting of Resources & Tools
So here is a potential idea
How can you make 15 resources into 45/60 resources.
Well we know that if forge is unsuccessful - you basically get around 65% - 70% of the resources back.
Around 70% of those resources are based on the number of % of resources that you put in.
E.G. If you placed all purple resources into the forge it would = 100% purple
Lets work on an example

With a 90% Resource discount you would need the following resources to create the above mentioned weapon
Resources required:
[Amethyst] 2/14
[Dragon Scale] 1/3
[Crystal] 3/22
[Gold Ore] 1/2
[Bronze] 1/5
[Diamond] 1/4
[Totem of Healing] 1/1
[Essence of Reaction] 3/25
[Vial of Charisma] 1/6
[Iron] 1/4
[Wood] 1/5
Total resources = 91
With 90% Discount = 16
Fail should give around 64 resources back
45 should be Red if the 16 resources were all/100% red
This would mean that the only tool that should be used is the -50% resource.
What would need to be tested is - if the forge starts - is the 100% the same if the forge is cancelled after a few seconds - or if the forge would need to be unsuccessful?
Experimentation can be done with purple resources - and the 40% costume & pumpkins to work out the variables