They do little to no damage when blocked with a previous zone's max upgraded shield. Once blocked they hover just long enough to one shot them with the previous zone's weapon.
If they were slower than your boat, they would not be very difficult, or if you could just outrun them on foot, why not ask for that?

They are not that bad -- you may even come to love them. The learning curve is rough and I get it, most of us got whacked by one or had our boat sunk by one during the learning process.

Why love them?
- they are easy to kill, very low armor and health, shield&hit is easy, shoot them is easy if not aggroed yet.
- they drop a very useful item, I can't get enough
- they kill everything on boarder zones, leaving loot for you by the chest full
- they make more noise than just about anything else, so its hard to not know one is near
- its rare to get more than 2 at once and they don't coordinate.

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if these are triggering you, the tar babies deeper in are going to be well fed.