Here is the full list of all 15 Tembo the Badass Elephant achievements.
You obtained 99 Peanut Butter Jars. I mean, that's a lot of Peanut Butter.
You obliterated every last PHANTOM enemy in or around this fair island!
You accomplished all of your Missions. You did it all. You are a supreme soldier. WE SALUTE YOU!
You rescued all the civilians in or around this island.
You rescued all the civilians in a zone.
You destroyed all the PHANTOM enemies in a zone.
You defeated the PHANTOM Commander and thwarted the PHANTOM invasion!
You obliterated the third PHANTOM Dome.
You demolished the second PHANTOM Dome.
You destroyed all the PHANTOM enemies in a stage.
You destroyed the first PHANTOM Dome.
You smashed the PHANTOM Lock.
You rescued all the civilians in a stage.
You obtained 10 Peanut Butter Jars.
Your training is complete.