A key problem in kaw is how to make the most gold given limited resources (time, gold, nobility, etc). Generally, the most efficient way to use health crystals is on the best paying premium eb on the best promos of the year (usually ata day and black friday), which will double the pay of premiums Hexavia the Ravenstorm and Hexavia the Illuminated are tied for the best paying epic battles, which are around 40% better than Netherking - though not everyone is able to acquire chimes for HTR or drums for HTI To maximize efficiency, I would recommend (and personally do this) to only xtal during these short promo windows. For whether to use spies or not - hansels get around 30% of their total gold from spy actions. It is generally recommended to use spies if you are a hansel with a relatively small number of xtals to run, and to only use 50% of your spy bar. Ultimately, it depends on your bottleneck - whether that be your crux chests, your chimes/seals, the number of xtals you have, or the amount of time you have to run xtals. If you want to optimize things even further, we can take a dive into game mechanics. Epic battle pay is solely based on If you are at max plunder The epic battle you're hitting Your buildings Any plunder bonuses you may have This means your bfa, equipment, damage done to the epic battle are all irrelevant to payout. Given this information and that it costs resources to open premium epic battles and boost plunder (lamps, battle cry) - you actually want to MINIMIZE the amount of damage you do to epic battles. A large hybrid will usually get 80-120 xtals on each HTR/HTI doing around 800-1100 damage an attack. If you try to lower your troop attack as much as you can, you can get to as low as 40-150 damage per attack, with the potential to run 500-1000 xtals per eb (the bottleneck will usually be the timer of the epic battle), making the nobility cost to open these premiums negligible. to get to 40 dmg a hit, you will need around a 150m raw troop attack stat (not cs) - which requires a tremendous amount of prep work Checklist of things to do Destroy all troop buildings except a lvl 1 elven temple on hoarfrost lands trade away all tradable charms (to an alt ideally) Have all allies giving more than 10m troop attack hired off Avoid the furniture achievements from lvl 10 -> 11 upgrades Unequip all equipment If you can manage to pull this off, you can run the most efficient xtals possible in the game. To give a sense of what is possible - with two build complete hansels with this setup hitting HTR on 100% promo with 300% crux, you can get up to 1000Q per eb
If you manage to minimize damage on the BC hansels you'd want to not use any spy bar at all since that would be a ton of extra damage, I assume? (I dont have a bc hansel)