Hello !
Actually, i prefer to see that as a chance for those who can not explore or participate to the events a lot (and everybody else too). Three times a year (or more, or less x) ), they could have the opportunity to make a nice trade, and not a trade with only many little ranks creatures... The way to try to find a creature they dream of, even if she is more rare than their usual duplicates.
I completely understand your feeling. At first I was divided, so for january i set a trade that i assumed was worth, but that was not at all ! When february started, I felt obliged to send more creatures to this player. So for february i set a more generous trade, but when the rarity finally fixed... The same.
(so i was very happy to find the one of august, because i'm not owning enough duplicates to make an adjustment this month
)
They are mysticals. Only few ones are distributed, so it's pretty rare to have one or two duplicates to put in the bank. As everybody is looking for, the rarity never decreases. I understand that if you are not picky and trade your high ranks creatures easily, you feel that sad, but maybe if you try to see that like a chance for new players to find older creatures you could feel better ?
As you said, there will be battles, and again many possibilities to find this destrinos, so i hope you will soon ! ❤
(also, if i "scratch" your language, do not hesitate to correct me, because sometimes i'm very bad and i don't want to say something wrong ^^')