Hello! I just downloaded this game a few days ago and I really, really enjoy it. Usually I muck around for a month to get my bearings but for this game I'd like to understand the game a little better and know what I'm doing so I can get the most enjoyment from the get go.

Is there a beginner's guide?

If not, can someone answer me a few questions please?

1. Do you need to keep the heroes in inventory for the Story bonuses or is it just like a checklist and I should discard them?

2. Is there a tier list? I see I get a Hero Selection ticket and I'd love to pick correctly.

3. Should I be working to upgrade my 5 star heroes? I have an Executor Asura 5 and Red Ghost Helen.

4. Should I be working to upgrade 4 stars? I have a Sweeney and some others but don't know if I'm supposed to be gathering stuff for them.

5. I have With the Giant Cat, Ashley Iruna 6 star...is there a list of units that work well together?

6. How do you merge units to get upgraded units. A lot of games use this feature but I don't see where to do it or how.

Thanks to anyone who takes the time to answer even one of these, I appreciate it.