It is a game that is like fishing in a barrel, but more stimulating mentally.
( It ( ( is ( ( a game ) ( that ( is ( like ( ( ( ( fishing ( in ( a barrel ) ) ) , ) but ) ( more ( stimulating mentally ) ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (PRP It)) (VP (VBZ is) (NP (NP (DT a) (NN game)) (SBAR (WHNP (WDT that)) (S (VP (VBZ is) (PP (IN like) (S (VP (VP (VBG fishing) (PP (IN in) (NP (DT a) (NN barrel)))) (, ,) (CC but) (VP (ADVP (RBR more)) (VBG stimulating) (NP (NNS mentally))))))))))) (. .)))
It is very different than a game such as fishing in a barrel.
( It ( ( is ( very ( different ( than ( ( a game ) ( such ( as ( fishing ( in ( a barrel ) ) ) ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (PRP It)) (VP (VBZ is) (ADJP (RB very) (JJ different) (PP (IN than) (NP (NP (DT a) (NN game)) (PP (JJ such) (IN as) (NP (NP (NN fishing)) (PP (IN in) (NP (DT a) (NN barrel))))))))) (. .)))