Zamus has some range. A thing that is true about ALL character with good projectile spam is that it forces you to do the approaching, which makes things more difficult. Zamus, imho, has a neat approach game.
Her fsmash actually spaces farther than just about any move in the game, and the stun shot, over-B, and grab also all give you almost as good long distance options. Getting close to a projectile spammer, is usually best done by mixing up short hops, shielding, spotdodging(very useful), and crawling. About crawling- she can be slow to go into a crawl sometimes, however she can go directly from a land to a crawl animation with 0 lag in between, so often after a shorthop you can crawl under certain projectiles for a bit. The trick to beating a good projectile spammer/camper as ZSS is having patience avoiding the projectiles, and getting into just that range where you're moves reach but theirs do not. A simple example- dashing towards pit, spotdodging an arrow out of the dash just within range of an fsmash, and then fsmashing with the tip right afterwards. After that, use ZSS's speed to get under him or keep him off balance.
When you mix it up to match it up with what they do and to not be too predictable, you'll find that you can move around and just space better than these projectile spammers and get them w/ you're superior range over and over.
