\documentclass[tikz,border=10pt]{standalone}
                        \IfFileExists{newpxtext.sty}{\usepackage{newpxtext,newpxmath}}{}
                        \linespread{1.10}
                        \usetikzlibrary{shapes}
                        \usetikzlibrary{arrows.meta}
                        \usepackage{graphicx}

                        \begin{document}

                        % TikZ code with built-in styling for game trees
% TikZ libraries required for game trees
\usetikzlibrary{shapes}
\usetikzlibrary{arrows.meta}

% Style settings for game tree formatting
\tikzset{
    every node/.append style={font=\sffamily\itshape},
    every text node part/.append style={align=center},
    node distance=1.5mm,
    thick
}

% Built-in macro definitions for game tree drawing
\newdimen\ndiam
\ndiam1.5mm
\newdimen\sqwidth
\sqwidth1.6mm
\newdimen\spx
\spx.7mm
\newdimen\spy
\spy.5mm
\newdimen\paydown
\paydown2.5ex
\newdimen\treethickn
\treethickn1.0pt
\definecolor{chancecolor}{RGB}{117,145,56}
\definecolor{playeronecolor}{RGB}{234,51,35}
\colorlet{playertwocolor}{blue}
\colorlet{playerthreecolor}{orange}
\colorlet{playerfourcolor}{purple}
\colorlet{playerfivecolor}{cyan}
\colorlet{playersixcolor}{magenta}

% Game tree content from /home/docs/checkouts/readthedocs.org/user_builds/gambitproject/checkouts/936/catalog/img/books/shohambrown2008/fig5_9.ef
\begin{tikzpicture}[scale=0.8
  , StealthFill/.tip={Stealth[line width=.7pt,inset=0pt,length=13pt,angle'=30]}]
% \draw [help lines, color=green] (-5,0) grid (5,-6);
%% player 1 name 1
\def\playerone{1}
%% player 2 name 2
\def\playertwo{2}
%% level -2.0 node 1 player 1
\draw [line width=\treethickn] (0,2)
   ;
%% level 18.0 node 1 xshift -1.9375 from -2.0,1 move A payoffs 1 0
\draw [line width=\treethickn,color=playeronecolor] (-1.938,-18)
   node[below,yshift=0.1\paydown,color=playeronecolor] {$\mathsf{1}\strut$}
   node[below,yshift=-0.9\paydown,color=playertwocolor] {$\mathsf{0}\strut$}
   -- (0,2);
\draw (-0.969,-8) node[left,xshift=-0.5mm,color=playeronecolor] {A\strut};
%% level 2.0 node 1 player 2 xshift 1.9375 from -2.0,1 move D
\draw [line width=\treethickn,color=playeronecolor] (1.938,-2)
   -- (0,2);
\draw (0.969,0) node[right,xshift=0.5mm,color=playeronecolor] {D\strut};
%% level 18.0 node 2 xshift -1.875 from 2.0,1 move A payoffs 0 2
\draw [line width=\treethickn,color=playertwocolor] (0.062,-18)
   node[below,yshift=0.1\paydown,color=playeronecolor] {$\mathsf{0}\strut$}
   node[below,yshift=-0.9\paydown,color=playertwocolor] {$\mathsf{2}\strut$}
   -- (1.938,-2);
\draw (1,-10) node[left,xshift=-0.5mm,color=playertwocolor] {A\strut};
%% level 6.0 node 1 player 1 xshift 1.875 from 2.0,1 move D
\draw [line width=\treethickn,color=playertwocolor] (3.812,-6)
   -- (1.938,-2);
\draw (2.875,-4) node[right,xshift=0.5mm,color=playertwocolor] {D\strut};
%% level 18.0 node 3 xshift -1.75 from 6.0,1 move A payoffs 3 1
\draw [line width=\treethickn,color=playeronecolor] (2.062,-18)
   node[below,yshift=0.1\paydown,color=playeronecolor] {$\mathsf{3}\strut$}
   node[below,yshift=-0.9\paydown,color=playertwocolor] {$\mathsf{1}\strut$}
   -- (3.812,-6);
\draw (2.938,-12) node[left,xshift=-0.5mm,color=playeronecolor] {A\strut};
%% level 10.0 node 1 player 2 xshift 1.75 from 6.0,1 move D
\draw [line width=\treethickn,color=playeronecolor] (5.562,-10)
   -- (3.812,-6);
\draw (4.688,-8) node[right,xshift=0.5mm,color=playeronecolor] {D\strut};
%% level 18.0 node 4 xshift -1.5 from 10.0,1 move A payoffs 2 4
\draw [line width=\treethickn,color=playertwocolor] (4.062,-18)
   node[below,yshift=0.1\paydown,color=playeronecolor] {$\mathsf{2}\strut$}
   node[below,yshift=-0.9\paydown,color=playertwocolor] {$\mathsf{4}\strut$}
   -- (5.562,-10);
\draw (4.812,-14) node[left,xshift=-0.5mm,color=playertwocolor] {A\strut};
%% level 14.0 node 1 player 1 xshift 1.5 from 10.0,1 move D
\draw [line width=\treethickn,color=playertwocolor] (7.062,-14)
   -- (5.562,-10);
\draw (6.312,-12) node[right,xshift=0.5mm,color=playertwocolor] {D\strut};
%% level 18.0 node 5 xshift -1.0 from 14.0,1 move A payoffs 4 3
\draw [line width=\treethickn,color=playeronecolor] (6.062,-18)
   node[below,yshift=0.1\paydown,color=playeronecolor] {$\mathsf{4}\strut$}
   node[below,yshift=-0.9\paydown,color=playertwocolor] {$\mathsf{3}\strut$}
   -- (7.062,-14);
\draw (6.562,-16) node[left,xshift=-0.5mm,color=playeronecolor] {A\strut};
%% level 18.0 node 6 xshift 1.0 from 14.0,1 move D payoffs 3 5
\draw [line width=\treethickn,color=playeronecolor] (8.062,-18)
   node[below,yshift=0.1\paydown,color=playeronecolor] {$\mathsf{3}\strut$}
   node[below,yshift=-0.9\paydown,color=playertwocolor] {$\mathsf{5}\strut$}
   -- (7.062,-14);
\draw (7.562,-16) node[right,xshift=0.5mm,color=playeronecolor] {D\strut};
\node[inner sep=0pt,minimum size=\ndiam,draw=playeronecolor,fill=playeronecolor,shape=circle] at (0,2) {};
\node[inner sep=0pt,minimum size=\ndiam,draw=playertwocolor,fill=playertwocolor,shape=circle] at (1.938,-2) {};
\node[inner sep=0pt,minimum size=\ndiam,draw=playeronecolor,fill=playeronecolor,shape=circle] at (3.812,-6) {};
\node[inner sep=0pt,minimum size=\ndiam,draw=playertwocolor,fill=playertwocolor,shape=circle] at (5.562,-10) {};
\node[inner sep=0pt,minimum size=\ndiam,draw=playeronecolor,fill=playeronecolor,shape=circle] at (7.062,-14) {};

% Player color legend
\begin{scope}[scale=1,shift={(-3.4375,2.0)}]
\node[inner sep=0pt,minimum size=\ndiam,draw=playeronecolor,fill=playeronecolor,shape=circle] at (0,0) {};
\node[anchor=west] at (0.3,0) {1};
\node[inner sep=0pt,minimum size=\ndiam,draw=playertwocolor,fill=playertwocolor,shape=circle] at (0,-0.625) {};
\node[anchor=west] at (0.3,-0.625) {2};
\end{scope}

\end{tikzpicture}

                        \end{document}