\documentclass{beamer}
\setbeamertemplate{navigation symbols}{}
\usepackage{tikz,tikzducks}
\usepackage{tikzlings}
\usetikzlibrary{shapes.geometric,shapes.callouts,calc}
\begin{document}
\begin{frame}
\begin{tikzpicture}[overlay,remember picture]
\fill (current page.south west) rectangle (current page.north east);
\begin{scope}[shift={(current page.south west)},%
x={($(current page.south east)-(current page.south west)$)},
y={($(current page.north east)-(current page.south east)$)}]
\only<3->{\foreach \X in {1,...,84}
