Phase 10 is fun. It's kind of similar to Rummy & UNO
Yes. Phase 10 is very much like Rummy. You have to get sets and runs.
What do you think the the most difficult phase is? 
For me it is the one where I have to get 2 sets of 4.
Yeah, that one seems difficult. Have you seen the variations where there are more than 10 phases?
No I haven't. How is that Phase 10 different from the original?
It's like if Phase 10 continued on. There are are more phases like 1 set of 4 and 1 run of 5
That would be interesting. I've only played the original. I'll have to look into playing with more Phases.
There's a hard phase where you have 2 runs of 5.
Wow. That would be very hard.  I'll check it out and spring the new version on my family.