The Heist Mode is a cut game mode from Counter-Strike: Global Offensive.
Placing the brush entity on the map's wall allows the player to "plant" the bomb on the wall.
In the May 31, 2016 update, Convars that reference "slow money" were added, and are possibly related to the mode:
mp_slowmoney_enabled mp_slowmoney_maxmultiplier mp_slowmoney_minmultiplier mp_slowmoney_multiplierdisplayasbonus mp_slowmoney_rampbias mp_slowmoney_rampend mp_slowmoney_rampstart
In the November 28, 2016 update, a new untextured terrorist model named
tm_heavy_riot was added to game files. It is possible that it is related to the game mode.
In the May 23, 2017 update, the above model was removed from game files.
- func_bomb_target on Valve developer Wiki