iPhone review of the day: Sentinel 3: Homeworld - tower defense done right

On iPhone
Game: Sentinel 3: Homeworld
Price: $2.99/£1.79
Size: 103 MB
Get it now at the iTunes store:US/UK

On iPad
Game: Sentinel 3: Homeworld
Price: $2.99/£1.79
Size: 103 MB
Get it now at the iTunes store:US/UK

Sentinel 3: Homeworld is a nifty little addition to a tower defense series that already rocked our world, and follows a theme we've been noticing more and more in the tower defense genre: movement. While most tower defense games give you the power to place stationary defenses (or to send units walking in a straight line if it’s a 2D, linear affair like Cartoon Wars 2), Sentinel 3 gives you a hero unit, the commander, to order around. It’s a game-changing touch.

On top of strategically planting mounted machine guns, missile launchers and bomb-droppers on the edges of your enemies' linear path, you'll have a mobile, multitasking walking tank at your disposal as well. The ED-209 lookalike rests in the battlefield, so it's vulnerable to enemy attack. Protecting your big bot is as important as protecting the barriers he's meant to defend - if he goes down, the walls fall, enemies flood through, and you're hosed.

It may sound arbitrary, but having an essential ally to cover adds a surprising level of tension and complicates a genre we thought we'd solved completely. Barriers aren't very sturdy, so you'll have to take the brunt of the damage on the commander unit. We regularly moved from one vulnerable gate to the other to grab a group of enemies' attention, sponge up some damage, fend off the horde, and repair the dying door. Again, this is in addition to the basic strategery of making smart moves, like plopping enemy-slowing turrets on corners, and dropping bombs in areas where baddies bunch up.

The commander is where you'll invest a lot of your earnings from winning battles. Abilities like mobility and repair aren't available right off the bat, and when you finally access 'em they're hardly the solution to your problems - they just lighten the heavy load that comes with 40 waves of evil, straight-line-walkin' monsters, bugs and bad guys.

As a series, Sentinel is persistently fantastic. Sentinel 3: Homeworld is a nice addition to this quickly booming iOS franchise, and we’ll happily stick with its challenging, involving monster murder grinder until the next sequel steps it up again.

Mar 2, 2011