It triggers whenever you play a land, as well as whenever a spell or ability puts a land onto the battlefield under your control
("Destroy" effects and lethal damage don't destroy it.) If Darksteel Colossus would be put into a graveyard from anywhere, reveal Darksteel Colossus and shuffle it into its owner's library instead
Cloud, Planet's Champion** Cloud, Planets Champion is a perfectly acceptable Boros Equipment commander with his on your turn protection and equip cost reducing, but fails to be exciting in any way after weve seen roughly a thousand Boros equipment commanders
This cinematic ending to the series absolutely delivers, Aang uses all the lessons he learned and you see Azula and Zuko in the fight of a lifetime
For example, you'll get rewarded for killing monsters X times and collecting Y number of items, but you'll have to come back many times to get all of the rewards