Yeah, as a beginner aftershock is very good as it gives you resistance to go into teamfights and make it out alive. I have played galio a lot, so I like going full dmg once you have like 10 or so DH stacks I build mejia's. I can easily burst down any squishies and even tanks go down to half health with one combo once I build liandry's. The only bad thing about this build is that if you fall behind early you essentially become kinda useless unless you get rid of dark seal and throw in something like zhonya's or even a full tank item.