As players, we've no objection to exploring a global we're not able to significantly influence. If the enemy doesn't see sneaking on him from behind or his side, then the guy can not cry in the market to alert his comrades nor is he going to have a chance to fire his weapon. Comparisons with Tomb Raider are in reality off here, because depth of puzzles and progress is more shallow than the adventures of Ms Croft, with the action only stopping less than marking which place to go with a big neon sign.