I bought Magic 2014 on Steam a long time ago, finally giving it a crack...seems really simplified compared to the real game so far...not seeing any of these three coloured cards, and not seeing much delve, morph and other mechanics that are dime a dozen in the drafts I've done so far.
Well yeah, the three color cards and those mechanics in that combination are unique to Khans of Tarkir. Each block has its own mechanics and themes. While core sets are indeed simpler (though it's misleading to say they're not the real game), the previous block, Theros, did not have any three color cards (though it did have a single five color card) and had a completely different suite of mechanics than Khans of Tarkir, with the exception of "evergreen" mechanics that are expected to be in every set, like trample and lifelink.
EDIT: Oh, the Steam reference probably means you're playing Duels of the Planeswalkers 2014, not drafting Magic 2014. In any case, that game is meant to be an introductory product.
EDIT: Just because, a guide to the mechanics of the previous block.
Theros:
Bestow allows you to cast a creature either as an enchantment creature, or as an aura enchantment that you can attach to another creature to boost it. If this aura ever becomes detached from the creature, such as from the enchanted creature dying, then it turns back into an enchantment creature.
Heroic creatures get an extra benefit if you target them with spells, being better suited for the godly gifts you bestow unto them.
Monstrosity abilities can only be activated once per game (per instance of that creature), but they can be used to make your creature huge or otherwise turn the game around. This represents that moment where it seems like the hero has defeated the monster, but it turns out that wasn't even its final form.
Your devotion to a color increases as you have more mana symbols of that color in the casting cost of your permanents. Basically, the more you stick to one particular color, the better. Gods are special creatures that, well, only become creatures if you show your devotion to their colors enough.
Scry allows you some limited control over what you will draw next. If you don't like what you see, you can put the cards on the bottom of your library, and otherwise rearrange the cards you see however you like.
Born of the Gods:
With tribute, your opponent is the one to choose which evil he or she would prefer, either making your creature bigger, or making the creature angry. In truth, this was a pretty wonky mechanic, to Wizards' admission. This replaced monstrous, but they ended up replacing tribute with monstrous in the next set anyway.
Inspired represents the creature waking up from a dream or something; this mechanic never really felt like a good fit in this block, IMO. Anyway, something happens when the creature untaps.
Journey into Nyx:
With constellation, each enchantment that enters the battlefield will trigger an ability, encouraging you to play decks filled with enchantments.
Strive spells allow you to target any number of creatures, but you have to pay more mana for each one.