Mass Effect 3: Charting the Plot Points

IGN brings us a closer examination of the bigger decisions we made during Mass Effect and Mass Effect 2, and how they might play a role in changing the plot of Mass Effect 3. For example:
Background: Urdnot Wrex is by far the most bad-ass character in the Mass Effect franchise. A true Krogan, his thirst for battle is evident, but he still has the common sense to know what's best for his currently withering species. After the Salarians inflicted a genophage to keep the overly-aggressive Krogan population down, the majority of Clan leaders still engaged in civil war, further ensuring their species' demise. Wrex, on the other hand, saw a better way: bunker down, band together, and focus on breeding until the population rises. Eventually he realized the majority of his brethren weren't ready for such a drastic change of mindset, so he returned to bounty hunting.

When Commander Shepard and crew landed on Virmire, they discovered a Krogan breeding ground designed to serve the Reapers. Wrex struggled with the idea of destroying the base, and therefore the cure to the genophage, but if you leveled up your persuasion skills you could talk the big guy down. Otherwise, you or Ashley put a bullet in his brain.

Why It Will Matter: If you saved Wrex from Ashley's trigger-happy finger, he shows up as the leader of the Krogan clans on Tuchanka. Grateful that you were able to talk him down, he assists you in your journey and even allows Grunt to become a member of Clan Urdnot.

If your speech level wasn't high enough to save him, or you just felt like killing something at that moment in time, you can expect that your mission to recruit the Krogan clans will be much more difficult. Also, what the hell were you thinking? Wrex is awesome.