OK, haha we can have a scrap metal these can be found on item boxes (regular item boxes have higher chance)
1.Ultra Gladiator = Fire/Electric Guardian, broken barrel, Bullets Storage 3,Rockets Storage 3,Scrap Metal, Essense, Repair Kit 7, Broken Window
2.Galaxus Model A =any galaxus models + bullets storage 4 + physical resistance module (6 resistance)
3.Cannon Feet = Golden Springs/ultra stompers/etc + Armor Plating 7 + 5 scrap metal + 2 essense + 1 broken barrell
THINK MORE xD hahaha
Scrap metals are cheapest junk items they can be buyed by 100 sm
Essense 300 sm
other junk items can only be found in item boxes
Chances of junk items appearing in item boxes
Item box 20 % junk items
Silver item box 7,5% junk items
Gold item box 1% junk items

It Would be Really Great if you can Build Mythicals...
Of Course you would need alot of stuff to build them ~Theoreticaly speaking
Maybe some Tokens too

For Example
Peircing Shotgun Mk1 needs 6 Shotgun X mark I's, "Scrap Metal", 20 Tokens


^Just Random stuff i thought about

Added poll

I think its like this = 3 Shotgun X mark I's, 3 Scrap Metals, 4 Essense, 2 Wiring, 20 Tokens, 1 physical Resistance drainer (dont care if its epic or common)

Any more responses?

Hmm an interesting concept to be completely honest. I think it would give the game far more customization but would this create balancing issues in some aspects. That is the main concern. However until someone says an issue with this which I can not see I'm going to vote yes.

Balancing issues? what? It would make many peoples get good items by just buying many boxes and buying junk items?

Well yes with balancing though there may be one combination which is too easy to get etc and it is more powerful than the rest just little things like that. Obviously these are for developers to work out and for the core of the suggestion not exactly major to be discussed at the moment.

Building items tules
1.You must use specific recipe to build an item. These can be found in hard and insane missions. You collect them by clicking / tapping them. (OF COURSE LOL) Though you still can build items without recipes, but wrong items will cause these items became one random junk item.
2. You can only build items if you are at least level 15. Though building legendary items and mythical items need to be at least level 30.
Mythical items need some tokens to build. ( I agree ACERCORE! )
3. Junk items can be fused too. (er,...)