How Do You Reply to Deadend Text?

Recent Example:
Talking with a friend, he mentions playing Pokemon Yellow. Reply with "Oh I loved that game" etc etc and ask how far he's gotten. "Just training pokemon in Viridian Forest because I'm OCD and need them all to be lv 10". Ask how many he's training. Reply? "6".

I have no idea how to continue this conversation without sounding super nosy. So things like this usually drop off and the conversation just ends. It happens a lot. Feels awkward.

How fix?

Change the sub-topic if it doesn't feel too nosy.

"What pokemons are you training?"
"Can you breed in Yellow?"
"What did you have for dinner?"
"I saw your new fb pic, is that girl with you your gf?"

What would feel REALLY nosy would be along the following lines:
"Hey, how were you today?"
"Fine."
"Busy at work?"
"Yeah."
"What're you doing?"
"Nothing."
"Today I almost got raped on the street."
"Cool story, bro."

Try bringing something else up? At least you don't have to come up with a response to "lol".

Or, maybe he is too busy training his Pokemon and you should leave him alone.

Just go with cool and either find a way to continue the topic at hand (which ones, etc) or bring up something else you have a mutual interest in (plans for this weekend, how's life in general, etc). Or branch it but stay on the similar topic (are you going to get a newer game, any other games you're playing, w/e).

"Six? That must take a while." Or, "Why so many?"

Or something along those lines. I don't know.

Changing the subtopic like that makes me feel nosey, and the conversation starts to feel one sided. (His answers aren't super short, but no prodding of any kind.)

I'll try sub topic changing next time I hit this wall, and see how it goes. If it starts to feel one sided, I'll try for an exit. "You sound busy, ttyl" or something.

Thanks guys.

Changing the subtopic like that makes me feel nosey, and the conversation starts to feel one sided. (His answers aren't super short, but no prodding of any kind.)

I'll try sub topic changing next time I hit this wall, and see how it goes. If it starts to feel one sided, I'll try for an exit. "You sound busy, ttyl" or something.

Thanks guys.

Well, if you do want to keep up the conversation, you have to be involved. The fine line between being involved and being nosey is yours to define. For a better chance at receiving response, you should try to scratch where it itches, not just shooting in the dark.
Like if he's stated that he's OCD about training, you can ask what his objective is regarding the final levels of his pokemons.

"Tried out the recent one yet?"

Also, another way would be to ask questions that require more than a one-word response. Might take a while to think of, but it's a good way to keep the other person involved while avoiding that awkward dead-end.