Using a pistol, shoot and destroy waves of insects to protect the sugar cube! Then upgrade your weapons, buy new weapons or buy turrets with the money you'll gain from each kill to defend against more dangerous bugs.
You'll play as a miniature bug exterminator with the tricky task of defending a sugar cube (probably for a cup of tea) in a giant kitchen. As the waves progress, the easy-to-kill woodlice are soon replaced with stronger bugs like ants, spiders, snails and more. Make sure to purchase the penetrating upgrades for your weapons or you'll be overwhelmed by stag beetles that have hard shells that take a lot to destroy.
Choose between shotguns, assault rifles or rocket/grenade launchers to best kill the bugs. If it gets too much, make sure to buy some turrets to help with your defence. Turrets will become crucial as you reach the higher waves. (The Bug Zapper will be especially useful for swarms as its electric attacks cause splash damage to multiple critters.) Upgrading the towers will make them more powerful!
Eventually, you'll be faced with bosses like The Colossal Beetle or The Caterpillar Army so make sure your defence is top notch to survive these dangerous bugs.