I am using a customised set-up as shown below for my title and need some help reducing the space between the top of the page and the "title" which in my case is defined by a "chapter" environment.
\documentclass[12pt,a4paper]{report}
\usepackage[margin=0.75in]{geometry}
\usepackage[latin1]{inputenc}
\usepackage{amsmath}
\usepackage{amsfonts}
\usepackage{amssymb}
\usepackage{multicol}
\usepackage{titling}
\usepackage{xcolor}
\usepackage[explicit]{titlesec}
\setlength\columnsep{50pt}
\setlength{\droptitle}{-5pt}
\author{The Doctor}
\title{\textbf{Mirko Vosk EDH}}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\titleformat{\chapter}
{\normalfont\LARGE\bfseries\fontfamily{uncl}\selectfont\filcenter}{} {0em}{#1}
\titleformat{\section}
{\normalfont\LARGE\bfseries\fontfamily{pbk}\selectfont\color{red}\filcenter}{}{0em}{#1}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\begin{document}
\chapter{``Rush of the Wild" R/G \, Aggro}
\begin{multicols}{2}
\section*{``Base" Creatures=04}
\begin{itemize}
\item 02 Rakdos Cackler (B/R) [2/2]
\item 02 Kalonian Tusker (GG) [3/3]
\end{itemize}
\end{document}
I would like for the document to be one page without changing my margins and shrink the space between title and top of page. Thanks!

\chapter, you can follow the instructions in How to decrease spacing before\chaptertitle? – Werner Dec 26 '16 at 18:50\maketitle. Is that intentional? You can edit your MWE in this question any time, to replace the MWE by a more targeting one. – Jan Dec 26 '16 at 19:50\titlespacingcommand oftitlesec. – Werner Dec 26 '16 at 20:05