Infamy rank 5 grind is so tedious

[Maahniac]

Are there any ways to do the Infamy rank faster? I feel like I'm missing something. Whenever I destroy boats and helicopters and so on, it's just a button-mashing nightmare that goes on forever. Even when using the Atomic Blast special ability. And sometimes when I need to leave the battle to eat fish and get health back, they lose track of me, and their healthbars have regenerated when I attack them again!? Can that be right?

Also, another question: Do I have to grind out the Infamy rank in the new DLC area, or can I go and do time trials, questers and so on in the areas of the main game, while still working towards this in those areas? The reason I'm unsure is that the Infamy rank 5 objective is listed under the new area.

Thanks.

 

[Adycakes]

I did it in the DLC area, but the game is a broken, unbalanced mess, I went through all this too just for the trophies to glitch. I simply don't understand how they have not seen these problems when developing or playtesting the game!

[FocusDR]

Personally I kept on rotating a certain area of the map where there’s a mixture of shallow, deep and open water. Boats and humans on foot, do circuits and attack everything on the way. Eventually personnel will come for you, take them out and quick as possible but search for more targets because the meter goes down when you’re not in view. 
it’s a slight grind but very doable

[Snake2410]

Bone armor maxed out, mutations - Hearty, Brutal Muscles, Reinforced Cartilage, and Tail Catapult all maxed out (so you'll have to complete the first one and get to level 35 to start out).  I also replaced Hearty with Healing Factor once I got it and maxed it out.

 

Then in the open area near the fast travel to the main area start biting and tail bashing boats. 

 

You'll be nearly invincible with all of the damage resistance and be able to take out boats really quickly with the tail whip.  Once they start throwing explosives and depth charges into the water try to grab them and throw them back.  You should rank up fast and get through them fairly quickly.  

 

I was at max before I even did more than discover the grotto.

[Kizer26]

If you've already progressed some in the DLC, the infamy grind is pretty quick with the Atomic Body. It gives you a projectile bite that shreds enemy vehicles, and once the timer is up you can eat the bodies left behind or some fish to recharge it. That with the Shadow Teeth for vampirism and the rest Bone (plus the organs Snake2410 mentioned) made getting 5 infamy super easy, barely an inconvenience.