Developer: Origin8
Genre: Tower Defense
Price: $2.99
Verdict: Extreme fun with hours of replay value.
Pro: The ability to pause the game and speed up the game is a great feature
Cons: Need to be able to remove new player notifications

Following the critically acclaimed Sentinel: Mars Defense, Origin8 has created another masterpiece with Sentinel 2: Earth Defense. The game takes place two months after the failure on Mars. Reinforcements never arrived and all personnel were lost. In preparation for the coming attack, your dropship, Sentinel, has been upgraded with an arsenal of devastating weaponry.

On a platform where tower defense has flourished, Sentinel 2 has taken some progressive steps in the evolution of the tower defense (TD) genre. Some of the new features within this game include the ability to build mobile attack drones, construct boosters that will increase fire rate, boost power to all surrounding offensive units, and it includes the upgraded sentinel weapon system I will call “Special Weapons”. As you can see from the below screen capture, there are four different Special Weapons from which to choose. As one progresses through waves of attacks, harvesting drones will be gaining vital resources to fuel these weapons. The more your drones can gather the faster you will be able to launch one of the four Special Weapons.

The monetary arrangement that is implemented in Sentinel 2 is similar to the vast array of other TD games. As the player destroys the aliens through waves of attacks, money is acquired based on the level of the attacking alien wave. With these funds one can construct a variety of weapons, i.e., turrets, grenade launchers, slowing pulse towers, electrical towers, and boosters. The player can also purchase repair drones that repair the gates if it takes damage from the attacks.

I have played many TD games before, and the format is much the same. You setup towers, wait for the next wave, and then build new towers or upgrade existing ones. However, Sentinel 2 provides a little more challenge than one might expect. For example, one of the alien waves when hit by the slowing pulse tower is teleported away from the attack. This allows it to bypass any of the defenses the player may have in place assuming the player has not built up defenses further down the line.

Sentinel 2 has definitely given me the most exhilerating experience I have ever had in a TD game. When lying in bed with closed eyes, you can feel and hear the humming of the booster generators going off and turrets firing at a break neck pace. You sense the smell of gunpowder and dust flying through the air as a grenade explodes in the trenches.  With aliens charging at you, as a last defense, you use a singular shock tower blasting beams of electricity over your head. Your hair is now standing on end.  The alien explodes and there you are alone but ready for the next wave.

The previous campaign on Mars was a failure. The colonies fell to ruthless creatures. Are you going to let them take over earth without a fight? Prepare your sentinel and dig in for the long haul, because you aren’t going anywhere soon.