I found this anti shark octopus. Could be useful to scary sharks from our waters.
If we could bread more of them and release near our beaches, rivers and channels , they should consume all sharks , or scary them away at least.
Octopuses are known to be very smart , and could be trained as easy as sheep dogs.
This one just come to the beach to greet some tourist and shake a hands with them.
It'd be better if it was a robot octopus, that could also file tax returns when not fighting sharks.
^^^ Macro, I hope you're taking the p!ss as it's a photoshopped image (and a poor one at that). Google 'giant squid' and that image used in your pic is shown in a much different context (and scale).
There have been a couple of giant squid brought up in local commercial fisho's nets over the years with the one in the article below going to the Melbourne museum for research 7yrs ago.
www.standard.net.au/story/726289/breaking-news-live-giant-squid-dissection/
They are already dead when they are caught up in nets which shows that they live waaay down in the deep and simply get moved by currents into shallower waters.
Keep up the ideas though, the blur between fiction and reality that your ideas are hinged on are always entertaining and thought provoking - just please don't use blatantly photoshopped images as it doesn't carry any weight with your ideas.