He keeps punishing your landings. Stay grounded a little more often. If he's playing super aggro all you have to do is shield and punish. You need to work a lot more on spacing, especially when you aerial his shield.
At :48, you should have just stopped DB. It was bound to fail.
Don't DS unless you know for a fact it will hit. You missed a lot of these.
At the very beginning, your spacing was good but then you started overcommiting to a lot of stuff, which got you punished. For example, you tried Fsmashing pika right after a well spaced Nair at :16. You could have just walked away and Dtilted or at least DB1 would be better. You took 30% for this.
Pivot grab is extremely safe and I always use it in a situation like :26. If he misses, you can't really be punished.
I kind of like the weaving in and out after :26 because I think it frustrates some people.
Marth doesn't have GR to anything on pika, afaik. He does have fthrow->fthrow->dthrow->tipper fsmash for 33% though.
1:47 skull bash has more lag than it appears to. You probably would have been safe going for tipper fair, uair, or nair.
Around 2:40 bad DS...Also **try not to keep going towards him and retaliating when you get hit.** A lot of players (not just Marth) have a hard time with this, but you just want to reset the situation when you get hit. This includes just getting the **** out of there. You did this around 2:50 and pretty much lost stage positioning and your stock because of this.
Hope this helps, and sorry for a late response.
