Here is a very basic back of the napkin comparison of two scenarios:
I. Chasing boxes (ring event this time) using second option (Ancient Spell, gold, “fair chance” to succeed)
II. Using the gold spent on the event elsewhere.
I would use my own experience/numbers, but the process is really simple, so anyone could utilize her/his own data instead.
Brief background (some numbers are rounded up for simplification purposes) : I am level 88 and need to pay 2200 gold for each attempt to open the box; tried some 120 times throughout the event winning 8 rings, or 3 indestructible items – Marauding Drake A/D 25/15, Nether Shade A/D 36/53 and Siege Cannon A/D 68/32. I also received a huge amount of “Sorrys”, a few allies I did not need, plenty of junk, such as Corpse Constructs, a bit of gold and some useful stuff, such as h points and bronze dragons. Estimated value of the useful stuff is around 44k gold (mainly because I am being generous). Gold used to open the boxes in the meantime had added up to 264k. After adding back estimated value of the “useful stuff” received from the boxes, my net loss amounted to 220K gold (not to counting some loss of sleep and general aggravation).
Scenario 1 – 3 indestructible units with cumulative A/D 119/90
Scenario 2 - for simplicity sake, I don’t consider here lost benefits/opportunity costs of buildings upgrade/construction, just an A/D values of equally indestructible units – generic weapons and armor that could be bought in the store for gold. NB: Most players I observe, including myself, tend to have more than enough fighting units (beasts, infantry, etc.), but not enough weapons/armor as per their respective full army size stipulated by the number of allies they bring to the field. In my own case, with a full stable of 440 allies allowed at my level, I could bring 1320 fighting units, which I have many times over, as well, as 1320 of each weapons and armor, yet I have got only 943 of each…
220 K gold would allow me to purchase 10 Maces of Destruction (weapon) at 11k gold and A/D 9/17 each, together with 10 Knight’s Platemails (armor) at 11k gold and A/D 7/19 each, adding up to cumulative A/D for weapons being 90/170 and cumulative A/D for armor being 70/190. Taken together, combined item of armor and weapons that could have been acquired for 220K gold would have added 160/360 to my army’s A/D, MUCH BETTER, THAN A/D 119/90 I HAVE GOT FROM THE 3 INDESTRUCTIBLE UNITS I “WON” IN THE EVENT. Moreover, adding Berserker Minotaur (ring # 9 win) at A/D 47/63 wont change the outcome. To be fair, winning Devil Warlord (ring # 10 win) would indeed overturn the outcome above, especially considering its ability to earn 40% more h points in fights, but the probability of this win appears to be rather low indeed.
Conclusions, opinions and recommendations:
“Technical” conclusion: it makes more in game economic sense to play the game as usual, rather, than chasing the boxes, unless offered pay off is more attractive for the gamer
Personal opinion: It is just a game. If someone wants to be “adventures” and pay for boxes, indestructible, etc. with a play gold, or even with gems – it is a matter of individual choice – no biggie. I wont, but it is just my personal choice. I would definitely continue occasional “Rusty knife” – free opening option in a future – who knows
Recommendation: there is absolutely nothing wrong for the developers to try to maximize revenue in any way, including “boxing” events. It might be prudent for them, however to offer more attractive pay offs/better probabilities of success, so they would be perceived to be more “fair”. That would keep the base satisfied and more interested to participate (including using the gem options, however occasionally) thus providing win-win for everyone