Ichy is an annoying light blue Ichthyornis called a sharpbeak. Dil is a nearly blind teal green Deinosuchus called a big-mouthed bellydragger. They work as partners to catch their food to set aside their disadvantages. Ichy calls himself the eyes because he guides Dil and tells her where to go, and relies on Dil because he is too small to catch his own food. Dil calls herself the teeth, but despite her size she has bad vision and needs Ichy to guide her. The two constantly argue about who is better and say that they don't need each other.
Ichy is smarter and Dil is stronger. Also, Ichy is the leader and Dil is the follower.
In spite of being the main villains, they don't appear into the film about 23 minutes in and only have around 15 mintus of screen time.
The two are first seen inside a cave trying to eat Littlefoot, who was hiding in crevices. Just when they were about to eat him, his friends came to the rescue by pushing rocks at them. Ichy and Dil follow the gang to a river, and Dil tries to capture Cera when she falls into the water. Luckily, Ali dodges Ichy's attack and rides a confused Dil to rescue Cera and get to safety. Later, Ichy and Dil arrive a third time and chase their victims to a log over a ravine. Ichy captures Ducky, though Petrie tries to save her, only for Ducky to fall. Ducky is woken up by Spike and manages to grab a branch just when she was about to fall into Dil's mouth. Spike then pushes Ichy off the edge, where he almost gets eaten by Dil.
After another argument, the two decided they have finally had enough of each other and split up. Ichy is hit with Dil's tail and flung into the distance. Shortly after, Dil encounters a hungry Hydrotherosaurus and calls for Ichy as it chases her.