Well, the Colour of the Wonderful that appears at Chen's Market in Winter is determined by a match between one of the Farming Degree sub-category totals and the general Farming Degree Title points.
My latest experiment showed a Red Wonderful at Chen's Market at 6.00 a.m. one Winter morning. I needed to reload my game, as I was simply testing something and had not fed my animals... When I reloaded, I decided that I needed to use my Tools as usual, which would change the points in most categories, eliminating the specific set of circumstances that caused the Wonderful to appear.
When I went to bed finally in my 'permanent' game, I had, among other things, caught another Monkfish, skewing the point totals even further.
I usually have cooked to change point totals and have been able to obtain three Orange Wonderfuls by doing this and shipping a couple of fish if necessary. I therefore am fairly certain that the Orange Wonderful is linked either toto the Cooking and Fishing Titles.
Cooking one dish at a time, no Wonderful had appeared even after I had cooked 20 dishes.
I decided to try to manipulate the Fishing Total instead. I shipped one fish at a time until...
A Yellow Wonderful appeared at 6.00 a.m. at Chen's Market.
I therefore now believe:
Cooking = Orange Wonderful
Fishing = Yellow Wonderful
God only knows what match created the Red Wonderful. I do not have time to continue this research at this point in time. It took me three hours to produce the Yellow Wonderful at Chen's Market, so I will move on now to log more Events instead...
I have been trying to determine how to set the colour of the Wonderfuls that appear at Chen's Shop in the Winter season. Originally I thought that the Orange Wonderfuls were linked to the Cooking and Fishing Totals but each Wonderful has to be linked to a single category to match the Farming Degree Total.
It seems, after tiresome, endless testing that:
Mining Degree is linked to the Blue Wonderfuls
Farming Degree (use of Watering Can) is linked to the Green Wonderfuls
I still believe that the Orange is linked EITHER to Fishing OR Cooking
Another point. It appears that a Wonderful Piece is set to appear on 10 Winter at Chen's Shop. No matter how much I tried, I could not change that into a Wonderful.
Would love to have concrete results from other players where these matters are concerned. I had to stop testing due to lack of time.
Players need to remember that the use of the Teleport Stone will change the Farming Degree total. I did that by accident in my game, rushing over to feed my (forgotten) Pig using the Teleport Stone when I knew a Wonderful was set to appear the next morning with the totals I had achieved!
Meanwhile, I had to remind myself that NO Wonderful will have an effect if your Tool is not charged when you use it. This applies to the Brush as well. Placing Yellow Wonderfuls in the Brush will increase the Affection point value for each use but ONLY IF YOU CHARGE THE TOOL! I had been using the Brush daily and essentially wasting the Yellow Wonderfuls that were set in it, because I was not charging it each time. One automatically charges the Hoe, Hammer and Axe because the Yellow Wonderful/s increases the effect visibly, allowing you to till the Rice Paddy if you charge your Hoe, smash large Boulders if you charge the Hammer and chop stumps if you charge the Axe. Where the Ranch Tools are concerned, however, it is important to remind yourself to charge any Tools set with Wonderfuls. The effect in the case of an Orange Wonderful is visible when you obtain a greater yield, but that of a Yellow is more subtle, where Ranch Tools are concerned. Remember that the 2G that each Purple Wonderful gives will not accrue either if the Tool in which it is set is not charged...