side b to keep them out of quick draw, also ike is an easy target off stage for dedede so thats what i go for if i play him.
Ike doesn't have the best recovery options available to him. The only way he can get back is through his side b and up b. Depending on his situation, usually he only has one option. The best way to edge guard him is to find out what he does. Usually on a side b (taking out the fact it's a stage with a pillar in the middle) he will not attack out of it if he's trying to get back to the stage. This is your chance to knock him off and make it possible. Because the hitboxes on D3 are pretty big, dair, bair, and fair are all pretty reliable options.
If Ike is using an up b and his only chance is to reach the ledge, you can of course try and edgehog, but another approach may consist of you doing a dair. His hammer seems long enough to get through the initial sword part of it.
You'll learn that D3 is pretty good with making it hard to get back to the stage. Fly destroyed me by doing that constantly. Watching some of his and other good D3 people may help you on this technique.