My Lands: Black Gem Hunting

someone has to sell

http://mlgame.us/wiki/Wiki.jsp?page=Science

if you check this link, should answer your question

so it is better to build at night

A player’s rank can be found out by pointing at the player’s domain on the Kingdom Map or in the Ratings Window.

for more information:

http://mlgame.us/wiki/Wiki.jsp?page=Rank

your Upgrade 3 Trading Post(example), but the task is not fulfilled, Upgrade 3 Stone Quarry or 3 Woodcutter Cabin and ready

if you want to know how to demolish a ruin, ask me in the game

I also happened, just do it again, with some of the other things they ask