It’s all working as intended, here’s an example with my specific numbers.
155% bonus from VIP, Dragon Armor and Pet (so, total value of 255% base, or x2.55)
In explore 1 I get 303 gold after the battle, with 0 gold collected.
Meaning the base for explore is 303/2.55 = 118.824 gold per battle.
E1:
If i collect 100 gold during the battle, that’s a total of (118.824 + 100) x 2.55 = 558 gold per battle
If i collect 200 gold during the battle, that’s a total of (118.824 + 200) x 2.55 = 813 gold per battle
If i collect 300 gold during the battle, that’s a total of (118.824 + 300) x 2.55 = 1068 gold per battle
Now if we go up to explore 12, the base stays the same, but another 7.3 multiplier is added at the end for the difficulty, as shown in game when you select explore 12. The numbers would then change to:
E12:
If i collect 100 gold during the battle, that’s a total of (118.824 + 100) x 2.55 x7.3 = 4073 gold per battle
If i collect 200 gold during the battle, that’s a total of (118.824 + 200) x 2.55 x7.3 = 5935 gold per battle
If i collect 300 gold during the battle, that’s a total of (118.824 + 300) x 2.55 x7.3 = 7796 gold per battle
The same calculations are applied to PvP but the “base” fluctuates wildly, and there is (in ranked), no difficulty multiplier.
So, in a case of a PvP battle with the base of 2000 gold i am earning:
2000 x 2.55 with 0 gold collected, making it 5100 gold
2100 x 2.55 with 100 gold collected, or 5355
2200 x 2.55 with 200 gold collected, or 5610
2300 x 2.55 with 300 gold collected, or 5865
Cedric and any other gold buffing traits have worked this way for at least since I started playing the game, there is no funny business going on, it’s just how the numbers work. In PvP, my total multiplier is 2.55, meaning every 100 base gold extra gets me another 255 gold payout. In Explore 12, my total multiplier is 2.55x7.3=18.615, meaning every 100 base gold extra gets me another 1861.5 gold.