I will complete what 1330 just said to add more details
1. Yes, types depends on rarity but only with a reaaaally small factor. There is one hidden creature for 3 familiars so having a "familiar" is a little bit easier than a hidden but not really, it applies to really ancient creature (2010 and 2011 mostly). But mystical ARE particularly rare (well except for some exceptions that I can't explain during old years) and hard to get.
And 1330 is right, Palladin have two explorations a day.
Either, it only explains where does the creature comme from (a Shop creatures comes from Creatura, Quest creatures comes from an event...)
2. I completely agree. Do explorations! o/
3. Meeep! 1330 forgot creatures! You can earn a lot of stuff by exploring so don't give up just because it can be boring. I am here for 5 years and I still do a loooot of explorations when I have time.
Note that for certain events (like Snowball battle incoming at Christmas) you can also find (but it's always announced, read the news to know when it starts) some event items.
4. Levels is a functionnality that plan to be introduced in new features but, for now, it's pretty useless. You can earn some by exploring, taking care of your creature, when someone visits his pages and twice if it's someone unknown (like a visitor who clicked on your creature). Probably other ways but I don't use them if so.
5. The barrier for "well being" is 80%. Under, the creature just have more chances to have a bad event while exploring (and that's the ONLY factor that have any influence on what you fond in exploration, not type/rarity/stats can change that).
6. Good question! (really) Honestly? My creatures goes to sleep maybe twice a year. I only feed-explore-next creature and sometimes, if health goes to 20%, send to sleep, because I prefer my creatures to be well, but that's a perosonnal method of taking care of my pets
Sleeping is almost useless. Apart from giving you 100% in all stats when everything goes well.
If you have anymore questions, please, write them
You can also PM me anytime
Enjoy the game ~