TOLOCOMassage Gun Deep Tissue, Upgrade Percussion Muscle Massage Gun for Athletes, Handheld Massager Gun, Black

Q: Does this have the feature like the hypervolt that causes it to bounce off bone if you accidentally go over a bone?

That's not a feature... you aren't supposed to go over bone with it. It's rubber bouncing off bone, yes it will "bounce". Soft tissue only so it will "absord" the inpact

Q: Vibrate or pulse back and forth? I'm confused. I've used the hypervolt one briefly at the gym. Can you advise?

Back and forth at very high speed, and even at speed 1 of 4 extremely fast.

Q: Does it come with a warranty?

The user manual says the warranty is within 1 year from date of purchase if product fails due to defect in material or workmanship, they will repair or replace. There is a list of non covered reasons for warranty including 1) damage caused by accident, abuse, improper handling 2) Units subjected to unauthorized repairs 3) Units not used in accordance w/instructions 4) Damage exceeding cost of product 5) Deterioration of delivered product resulting from abnormal storage or safe guarding conditions.