In the last video, we applied IK Dynamics to our octopus' tentacles. In this video, we're going to prevent the tentacles from intersecting one another during the dynamic simulation by utilizing IK dynamics colliders. So here I have my octopus here. And if I hit Play and just rotate this guy around and have him do a little dipsy-doodle twirl, you can see that we have some intersecting going on of our tentacles. And that's no good because when we actually go to animate this, it's going to cause some problems if we have some intersecting geometry. Luckily, we have in our IK Dynamics tags, we have this "Collision Option." Now if we check that on to all of our IK tags here, we can now define objects that will then recognize and collide into the IK. So in this case every single one of these IK tags will need to have the other tentacle geometry in this objects field, so it doesn't collide into it. So, on this first IK tag, we need to make sure we don't actually put in the same geometry that we have the IK chain actually bound to. So we're going to select this one, this tentacle and this tentacle, and then for the next one we'll just select every other tentacle other than the one that it's bound to, and just keep going on down the line, again making sure we're not selecting the same geometry that that IK tag is bound to. And now each of our IK tags collider fields should be filled with three other tentacles other than itself. So great. Now, we can go and hit play, and let's see what happens. If I do a twirl again, you'll see that we have some popping going on, but we no longer have any more of the intersections going on. Now if I go really fast, you're going to see that we have a whole lot of crazy stuff happening, and that's not good either, right? So to prevent that, we can simply go into each of our dynamic IK tags here. And under the "Advanced", we have this "Step" option here. So what the "Steps" does is increases the level of dynamic and collision related calculations and just upping this number just makes for a more accurate simulation, especially when your objects are moving really fast. So maybe we can see if we can get away with the steps of two and let's have this guy do a little twirl around. And you can see that it's going a little slower in our viewport because it's up in the calculations, but we're no longer having that little spaz out that happened with the IK before. So I think we can get away with a steps of two. Now, all these other options in the "Collision Options" are pretty self-explanatory. The radius is just the radius buffer from how far out from the tentacle or the object geometry you want that buffer to be. So we can actually probably get away with a lesser buffer. And both friction and balance are pretty self-explanatory. You adjust the friction strength and the balance when two objects collide. So, now we can go ahead and animate this character and we won't have any issues with the legs intersecting one another by utilizing the IK collider options. So with our legs all rigged up for animation we can now move along to rigging our facial features.