According to the corrected patch notes, there should be +1 bonus jewel on regular rooms and +2 on boss rooms for every 4 dungeon levels.
As can be (barely) seen, the dungeon level in the screenshot is 7. However, the jewels of the day (diamonds) are still on their base value.
read the notes
Dungeon Level will also affect the rewards that can be earned in the Dungeon, so completing Dungeons on harder difficulties will give more rewards.
Shards +1 per level
Jewels +1 per level
Diamonds +1 per 10 levels
The Megaboss gives double rewards
I may repeat myself: This is not about the diamond bonus, but about the jewel bonus. Sundays jewels are diamonds.
Do you actually think, the developers intended the amazing increase from 20/20/30 to 21/21/32 as a reward for pushing the dungeon difficulty to maximum?
There is a separate rule for diamonds, why is it so hard to understand?
I am bloody sure they did. When did we get a huge plus ever in any resources? The community cried for years for a way to obtain forge scrolls, and we got recipes with horrendous costs gated behind a very scarce resource (cursed rune)
The developers do not care about you they care about money.
They definitely appeared that way in the previous Boss Dungeon mode. On colored days you’d get +20 Diamonds total from the 3 bosses, but on Sundays (due to lack of a colored jewel) it was something like +40 total.
There has always been a consistent, approximately 1:5 ratio between Diamonds and colored Jewels.
To clarify, Shards and Diamonds will remain unchanged in reward total no matter the day of the week. Which is why they are displayed in their own totals within the Dungeon patch notes.
So while Sunday is Diamond day, this does not change it’s reward increase total for this one day for descending a level.