Everybody has a different name for that position. Star, Striker, Nickel, Bandit, etc.
In today's football world, that guy has to be your best overall football player IMO, for multiple reasons.
1. He's almost always to the wide side of the field, so he has to be athletic in space. Has to be able to cover and tackle slot WR's and TE's.
2. Has to be smart. There's a lot of different elements/sets that he'll be presented with. Three WR sets. Two WR sets. Tight Ends. Wide spacing. Tight spacing. Motion. He has to know how to line-up versus all of that crap, in various coverages. On top of that, there's so many different route combos that he has to recognize.
3. He has to be strong enough to play at the point-of-attack. Not only will he be asked to defeat blocks on screens, but he may be asked to add-on to the LOS versus TE/condensed offensive sets. This is why you can't always use a traditional Nickel.
4. Depending on the coverage and front, he may be asked to show-up in the run fit. And it'll likely be from depth, so he's gotta be ready to run downhill and strike.
5. He may be asked to blitz. I send my Nickel/Star at least 5 times per game, maybe more depending on opponent. The element of surprise leads to a lot of sacks or TFL's. He can't be scared to come hard. (pause)
Ideally you'd like somebody in that spot who is a hybrid Linebacker/Safety type. Around 6'1"-6'3" and 210lbs-225lbs.
And then if the offense is in sure passing situations then you can slide him inside and put a true Nickel DB on the field.
