Hi there, I'm Matt Sergei (do call me Matt, plese) and can creae your animation -
can your provide more details:
1. Rifle scope - basically a circle that would move around a screen before centering on your character?
2. What character? Do you have it's shape/figure?
3. SVG probably allowed. Based on you need mobile devices support and for speed performance I would probably go with canvas (HTML5 element) instead.
Otherwise I'm a webmaster and developer for 26+ years, scripting web animations/charts/visualizations mere extensively in last 7+ years.
Regards and hope you're safe,
Matt