\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/913/catalog/journals/mor/vonstengelforges2008/fig6__Original_Layout.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);
\draw [line width=\treethickn,color=playeronecolor] (-3.5,-1.125) arc(90:270:0.375)
  -- (3.5,-1.875) arc(-90:90:0.375) -- cycle;
\draw [line width=\treethickn,color=playertwocolor] (-3.9,-3.625) arc(90:270:0.375)
  -- (-0.3,-4.375) arc(-90:90:0.375) -- cycle;
\draw [line width=\treethickn,color=playeronecolor] (0.9,-5.625) arc(90:270:0.375)
  -- (4.5,-6.375) arc(-90:90:0.375) -- cycle;
\draw [line width=\treethickn,color=playertwocolor] (2,-7.625) arc(90:270:0.375)
  -- (5.7,-8.375) arc(-90:90:0.375) -- cycle;
\draw [line width=\treethickn,color=playeronecolor] (-4.725,-2.745) arc(0.8:180.8:0.375)
  -- (-5.375,-10.005) arc(-179.2:0.8:0.375) -- cycle;
%% player 1 name 1
\def\playerone{1}
%% player 2 name 2
\def\playertwo{2}
%% level 0 node 1 player 2
\draw [line width=\treethickn] (0,-0)
   ;
%% level 1.5 node 1 xshift -a=3.5 from 0,1 move a
\draw [line width=\treethickn,color=playertwocolor] (-3.5,-1.5)
   -- (0,-0);
\draw (-1.75,-0.75) node[left,xshift=-0.5mm,color=playertwocolor] {a\strut};
%% level 1.5 node 2 xshift a from 0,1 move b
\draw [line width=\treethickn,color=playertwocolor] (3.5,-1.5)
   -- (0,-0);
\draw (1.75,-0.75) node[right,xshift=0.5mm,color=playertwocolor] {b\strut};
%% iset 1.5,1 1.5,2 player 1
%% % level 4 node 1 xshift -b=1.6 from 1.5,1 move L
%% level 2.75 node 1 xshift -b=1.6 from 1.5,1 move L
\draw [line width=\treethickn,color=playeronecolor] (-5.1,-2.75)
   -- (-3.5,-1.5);
\draw (-4.3,-2.125) node[left,xshift=-0.5mm,color=playeronecolor] {L\strut};
%% level 4 node 2 xshift 2b from 1.5,1 move R
\draw [line width=\treethickn,color=playeronecolor] (-0.3,-4)
   -- (-3.5,-1.5);
\draw (-2.7,-2.125) node[right,xshift=0.5mm,color=playeronecolor] {R\strut};
%% level 4 node 3 xshift -s=1 from 2.75,1 move S payoffs 0
\draw [line width=\treethickn,color=playeronecolor] (-6.1,-4)
   node[below,yshift=0.1\paydown,color=playeronecolor] {$\mathsf{0}\strut$}
   -- (-5.1,-2.75);
\draw (-5.6,-3.375) node[left,xshift=-0.5mm,color=playeronecolor] {S\strut};
%% level 4 node 1 xshift 1.2 from 2.75,1 move T
\draw [line width=\treethickn,color=playeronecolor] (-3.9,-4)
   -- (-5.1,-2.75);
\draw (-4.5,-3.375) node[right,xshift=0.5mm,color=playeronecolor] {T\strut};
%% % iset k
%% iset 4,1 4,2 player 2
%% level 5 node 1 xshift -c=.6 from 4,1 move c payoffs 0
\draw [line width=\treethickn,color=playertwocolor] (-4.5,-5)
   node[below,yshift=0.1\paydown,color=playeronecolor] {$\mathsf{0}\strut$}
   -- (-3.9,-4);
\draw (-4.2,-4.5) node[left,xshift=-0.5mm,color=playertwocolor] {c\strut};
%% level 5 node 2 xshift c from 4,1 move d payoffs 0
\draw [line width=\treethickn,color=playertwocolor] (-3.3,-5)
   node[below,yshift=0.1\paydown,color=playeronecolor] {$\mathsf{0}\strut$}
   -- (-3.9,-4);
\draw (-3.6,-4.5) node[right,xshift=0.5mm,color=playertwocolor] {d\strut};
%% level 5 node 3 xshift -c from 4,2 move c payoffs 0
\draw [line width=\treethickn,color=playertwocolor] (-0.9,-5)
   node[below,yshift=0.1\paydown,color=playeronecolor] {$\mathsf{0}\strut$}
   -- (-0.3,-4);
\draw (-0.6,-4.5) node[left,xshift=-0.5mm,color=playertwocolor] {c\strut};
%% level 6 node 1 xshift 2c from 4,2 move d
\draw [line width=\treethickn,color=playertwocolor] (0.9,-6)
   -- (-0.3,-4);
\draw (0,-4.5) node[right,xshift=0.5mm,color=playertwocolor] {d\strut};
%% level 6 node 2 xshift 2r=.5 from 1.5,2 move R
\draw [line width=\treethickn,color=playeronecolor] (4.5,-6)
   -- (3.5,-1.5);
\draw (3.75,-2.625) node[right,xshift=0.5mm,color=playeronecolor] {R\strut};
%% iset 6,1 6,2 player 1
%% level 7 node 1 xshift -u=.6 from 6,1 move U payoffs 0
\draw [line width=\treethickn,color=playeronecolor] (0.3,-7)
   node[below,yshift=0.1\paydown,color=playeronecolor] {$\mathsf{0}\strut$}
   -- (0.9,-6);
\draw (0.6,-6.5) node[left,xshift=-0.5mm,color=playeronecolor] {U\strut};
%% level 7 node 2 xshift u from 6,1 move V payoffs 0
\draw [line width=\treethickn,color=playeronecolor] (1.5,-7)
   node[below,yshift=0.1\paydown,color=playeronecolor] {$\mathsf{0}\strut$}
   -- (0.9,-6);
\draw (1.2,-6.5) node[right,xshift=0.5mm,color=playeronecolor] {V\strut};
%% level 7 node 3 xshift -u from 6,2 move U payoffs 0
\draw [line width=\treethickn,color=playeronecolor] (3.9,-7)
   node[below,yshift=0.1\paydown,color=playeronecolor] {$\mathsf{0}\strut$}
   -- (4.5,-6);
\draw (4.2,-6.5) node[left,xshift=-0.5mm,color=playeronecolor] {U\strut};
%% level 8 node 1 xshift -3r from 1.5,2 move L
\draw [line width=\treethickn,color=playeronecolor] (2,-8)
   -- (3.5,-1.5);
\draw (3.25,-2.583) node[left,xshift=-0.5mm,color=playeronecolor] {L\strut};
%% level 8 node 2 xshift 2u from 6,2 move V
\draw [line width=\treethickn,color=playeronecolor] (5.7,-8)
   -- (4.5,-6);
\draw (4.8,-6.5) node[right,xshift=0.5mm,color=playeronecolor] {V\strut};
%% iset 8,1 8,2 player 2
%% % level 4 node 4 xshift 1.02 from 1.5,2 move R
%% % level 6 node 4 xshift 1.02 from 4,4 move V
%% level 10 node 1 xshift -7 from 8,1 move e
\draw [line width=\treethickn,color=playertwocolor] (-5,-10)
   -- (2,-8);
\draw (-1.5,-9) node[left,xshift=-0.5mm,color=playertwocolor] {e\strut};
%% level 10 node 2 xshift f=0.7 from 8,1 move f payoffs 0
\draw [line width=\treethickn,color=playertwocolor] (2.7,-10)
   node[below,yshift=0.1\paydown,color=playeronecolor] {$\mathsf{0}\strut$}
   -- (2,-8);
\draw (2.35,-9) node[right,xshift=0.5mm,color=playertwocolor] {f\strut};
%% level 10 node 3 xshift -f from 8,2 move e payoffs 0
\draw [line width=\treethickn,color=playertwocolor] (5,-10)
   node[below,yshift=0.1\paydown,color=playeronecolor] {$\mathsf{0}\strut$}
   -- (5.7,-8);
\draw (5.35,-9) node[left,xshift=-0.5mm,color=playertwocolor] {e\strut};
%% level 10 node 4 xshift f from 8,2 move f payoffs 0
\draw [line width=\treethickn,color=playertwocolor] (6.4,-10)
   node[below,yshift=0.1\paydown,color=playeronecolor] {$\mathsf{0}\strut$}
   -- (5.7,-8);
\draw (6.05,-9) node[right,xshift=0.5mm,color=playertwocolor] {f\strut};
%% iset 2.75,1 10,1 player 1
%% level 11 node 1 xshift -s from 10,1 move S payoffs 0
\draw [line width=\treethickn,color=playeronecolor] (-6,-11)
   node[below,yshift=0.1\paydown,color=playeronecolor] {$\mathsf{0}\strut$}
   -- (-5,-10);
\draw (-5.5,-10.5) node[left,xshift=-0.5mm,color=playeronecolor] {S\strut};
%% level 11 node 2 xshift s from 10,1 move T payoffs 0
\draw [line width=\treethickn,color=playeronecolor] (-4,-11)
   node[below,yshift=0.1\paydown,color=playeronecolor] {$\mathsf{0}\strut$}
   -- (-5,-10);
\draw (-4.5,-10.5) node[right,xshift=0.5mm,color=playeronecolor] {T\strut};
\node[inner sep=0pt,minimum size=\ndiam,draw=playertwocolor,fill=playertwocolor,shape=circle] at (0,-0) {};
\node[inner sep=0pt,minimum size=\ndiam,draw=playeronecolor,fill=playeronecolor,shape=circle] at (-3.5,-1.5) {};
\node[inner sep=0pt,minimum size=\ndiam,draw=playeronecolor,fill=playeronecolor,shape=circle] at (3.5,-1.5) {};
\node[inner sep=0pt,minimum size=\ndiam,draw=playeronecolor,fill=playeronecolor,shape=circle] at (-5.1,-2.75) {};
\node[inner sep=0pt,minimum size=\ndiam,draw=playertwocolor,fill=playertwocolor,shape=circle] at (-0.3,-4) {};
\node[inner sep=0pt,minimum size=\ndiam,draw=playertwocolor,fill=playertwocolor,shape=circle] at (-3.9,-4) {};
\node[inner sep=0pt,minimum size=\ndiam,draw=playeronecolor,fill=playeronecolor,shape=circle] at (0.9,-6) {};
\node[inner sep=0pt,minimum size=\ndiam,draw=playeronecolor,fill=playeronecolor,shape=circle] at (4.5,-6) {};
\node[inner sep=0pt,minimum size=\ndiam,draw=playertwocolor,fill=playertwocolor,shape=circle] at (2,-8) {};
\node[inner sep=0pt,minimum size=\ndiam,draw=playertwocolor,fill=playertwocolor,shape=circle] at (5.7,-8) {};
\node[inner sep=0pt,minimum size=\ndiam,draw=playeronecolor,fill=playeronecolor,shape=circle] at (-5,-10) {};

% Player color legend
\begin{scope}[scale=1,shift={(-7.6,-0.0)}]
\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}