For office employees: an addictive retreat for your self-proclaimed tea-breaks! Great for de-stressing!
By having the choice of either a guy or gal for your main character, there is also a simple RPG element of level-up options (e.g. strength, accuracy, weight allowance) for your role-playing pleasure. The monsters are just mad in terms of numbers and their variety is interesting enough to grab your attention despite the repetitiveness sometimes.
*ALERT* - There is another ridiculously expensive(US$40!) game in the market named Invasion Grounds that is actually an exact rip-off of Alien Shooter. Be warned!
KingLim