Raskulls

This achievement is straight forward enough, like the description says you just need to stay in Frenzy mode for at least 10 seconds. There are plenty of ways of getting this achievement with relative ease but I believe 2 methods in particular stand out.

The first of which is to simply fill up your Frenzy Meter, you do this by collecting the little jars that are scattered throughout races. Once you've filled up your Frenzy Meter continue through the race until you reach a frenzy pool which you're able to stand in. When you find one pull "LT" to activate Frenzy and just stay where you are. As your Frenzy is used the pool will slowly add to it, it won't keep it at maximum but it should be enough to unlock this achievement.

However, if you are having difficulty with the above method there's another awesome way of unlocking this achievement. Once you've unlocked The Crown Cup Grand Prix playthrough until you reach the second race, there's a section of this stage where there a lot of frenzy jars close to each other. Simply move through these to keep your frenzy meter from depleting and you shouldn't have any trouble unlocking the achievement.

An example of these methods can be seen in the videos below.

* ^{Credit to Nave360 and MaxlockMark for the videos}

When you get to the first checkpoint level (5th level of the game) called Checkpoint Chaos, go past the first five checkpoints without using any Frenzy collecting whatever jars and bubbles you need to fill up your frenzy meter
Then right before you get to the sixth checkpoint hit to activate your frenzy.
There are a bunch of jars lined up allowing you to get this achievement very easily and more importantly, very early in the game.

The easiest way ive found is to do a Quick Race with two controllers. Make sure it's a level with presents. Keep picking up presents with controller 1 until you have a whistle. Have controllers 1 & 2 stand in a Boostie Zone (orange area with bubbles) until both frenzy meters are full. Now with controller 1 just press (LB) or (LT) to activate frenzy, then press (Y) to activate your whistle (which steals the other players frenzy). Ten seconds later it will pop.