File:Fusion-5-orig 1 orig.png

Summary
Fusion Forge: Page 05 Caption:

Select item you wish to sacrifice to upgrade your decoration item. You want to use fusion Parks and gardens which are useless for anything else.

Next, click on the icon to select the catalyst (not the plus sign, which is for making more of them). The difference between them is a chance at getting extra upgrade experience.

Click confirm button when selections are ready