Would be so nice since took FOREVER to upgrade training facility to level 20 to get more then just level 3 from 8 tries!! I mean at least 1out of 5 gees!! Makes me wanna quit the game completely and lot of other people I asked In chat have same issue 
According to this thread, 5* chances are 5%…
Training Camp lvl 20 - Global stats summary
And here, they talk about 3%…
I have to say either I’ve been extremely lucky or the gods are with me. I’ve had 27 tc20 pulls and have gotten a 5* and just pulled my ninth 4* hero. However the majority of my 4* heroes have been duplicates but they’re still better than 3’s
I’ve recently started training…first hero was Graymane and today I received Vivica.
Perhaps it’s random like so many toher things out there is EP land.
In the long term it does seem like 3-5%.
If you have two of them going nonstop that averages out to one a day.
In a year that averages out to around 11 to 18 5 star heroes.
Not bad if you keep them churning.
I’ve used my tc20 5 times. The 3rd and 5th time I got a 5* from it.
You just have to accept that random means you will have bad luck and good luck. Gotta hang in there and keep training.
Yeah it took me about 40 rolls to get my first 5 star from it.
The next week I got two more.
It’s free and it’s something you can do every day if you’re advanced enough to have built it.
It’s live everyone else is the game. You need patience or money…
I have my 5 heroes i want for now only level them up now. I conenctrate on troops for maxing them out, then i got to make training20 again.
Lol raging after 8 tries hahaha I did 51 pulls so far with 45 3* 
I had 80 tries before I got my first 5* out of TC20. It was a duplicate of one I already had. So were my next three after that.
It is working, had like 5 or 6 5* in about 150 tries. Have four tc20 training. So every day 2 pulls. But a lot of 3* indeed.
How many recruits does one need for a TC20 pull?
100 recruits needed.