Kent won $25\%$ of the games he played on Saturday. If he lost 12 games on Saturday, and no game ended in a tie, how many games did he win?
If Kent won $25\%$ of the games, he lost $75\%$ of them.  Thus if $g$ is the total number of games he played,

$$12=0.75(g)\Rightarrow g=16$$

So the number of games he won was $16-12=\boxed{4}$.