Gus and Slink Bradshaw are the only members of the Bollard Twins Gang who cannot be encountered in Pike's Basin hideout in single player.
Like Slink Bradshaw, pulling a gun on Gus when he is in Thieves' Landing will cause him to put his hands up, shout in shock and then run away.
Gus along with Julius Grimes, is one of the two members of the Bollard Twins Gang who will drag a victim during the "Wild Posse" random encounter. For the Bollards, they can do this encounter either in Thieves' Landing, which is extremely common, or through MacFarlane's Ranch, which is much rarer.
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