He is only 13 moths old. I wouldn't conceder this a bully mentality just yet. Most kids who can't communicate really well (talk) do other things to get your attention. My son is 14 months and has hit me before. I just sit him down and look him in the eye, and tell him no hitting isn't nice, and that it hurt mommy. And just repeat it if he does it again. Kids throw tantrums, my sons are notorious. I like to practice what I call the 3 P's of parenting. Persistence, patience, and perseverance. You may also want to talk to his Pediatrician maybe they can recommend some techniques. Most importantly breath, keep you chin up. 

At 13 months that is normal.  He wants something but doesn't have the words to express it.  I would hold his hands and say we don't hit.  I only slapped my kids hands if they were going for something dangerous or harmful like the outlet.  As for throwing toys, I would take the toy away and say we don't throw toys.  My ds is 4 and still throws toys.  He loses them, he knows it, it still happens on a daily basis.