why not just add step by step tutorial for a first test dagger
Which (dagger) also will give sense of first accomplishment and first money for selling first dagger
and you can Literally add feedback text on screen after few hit on cold metal
like "its too cold - Add some heat" or "its too hot and soft"
just add some obvious Indicator
For example temperature Bar should have not 1 line but Range of perfect and middle zone on it