An ink that changes colour when exposed to light, like an octopus does to match its surroundings, could one day be used for automatic camouflage.

The uncannily clever winner of Week 77 in 1994 — the only Invite ink ever for Dennis Goris. In this week's contest, you could try a combo like this, but your odds of ink are long.

An octopus in attack mode is the ocean’s version of a ninja. In the waters of the Mediterranean, these divers encountered an octopus. As they tried to get close, the octopus wasn't having it.