• Don't know, a price tag gets added to everything though so don't question it
• If you are talking about dragon points, they increase the higher levels you are
• For now it's free, if they taxed it they would of got so much backlash because they nerfed unit build times to begin with
• No it can't

People have been asking for the obelisk to save where it was instead of going back to the top and in the black market it does some funky stuff with which page its on and jumps around, they are still yet to be fixed

I like the idea of the progress bar for it, maybe add a 2nd layer to the lost arts bar (like craftsmen) 

thanks for all the info.

however, it'd be great to know the actual amount to pay to activate a bonus,

I would really like see the ability to trade in your dragon points for dragon marks at a certain ratio. Like how you trade gold/iron for amulets.

have only this for now

add lv2

Lord MRFREEZZZZ, here are answers on your concerns:

• The costs of activating your dragon with only Conventional Dragon Arts are free. However, activating your Dragon including one Arcane Dragon Art will cost you Dragon Marks. As far as I know activating your dragon will not require Sapphires.
• Yes, the higher your Dragon Art level, the higher the cost of Dragon Points if that's what you meant.
• It'll be free, except if you activate it with an Arcane Dragon Art. It'll cost a kind of Dragon Mark then.
• It cannot be extended.

Make sure to check the wiki as well; it's being maintained and updated by me! Here's a direct link to the Dragon Stone article.

About your suggestions, I'll make sure these are passed on.

Enjoy the game!

another suggestion: as is, the cost to refresh mana is constant. maybe it'd decrease, as the timer goes down.

now a couple suggestions: 

• every time one goes to the dragon arts tab, it moves back up to the first art, "dragon 1/1", which is so stupid! people have to scroll down EVERY time to reach the current art they're upgrading! since this is all flash-based, all it'd take is to change the variable for the movieclip state/location
  
  
• and maybe more importantly, please add an upgrade progress bar in the castle view! it's so annoying to have to open the dragon stone, go to the arts tab, scroll down to find out how far done is the upgrade. plus, i see no reason why it's the only feature without a progress bar, when everything else has one (mara altar, lost arts, buildings...)
  

It will cost Sapphires to unlock the 4th and 5th activation slots - no doubt there are other hidden costs because we will never earn enough Dragon Marks from tournaments to make it worthwhile

If you need any other information, the wiki provides it! 

i'm not concerned about the art discovery time, but the bonus activation time. 

usually, when it says "for free", it means it may not always be for free.
plus, it's obvious that the "For Free" is displayed dynamically, and can easily be replaced by a nice "For 1000 sapphires"