It usually goes like this: innovative new game creates genre, subsequent games flesh out the genre one iterative improvement at a time.

The tower defence category, though, has spawned both a segment of fiercely innovative newcomers and games that compete on strength of execution alone.

Tower Raiders 2 falls more into the latter grouping than the former, but still manages to bring a number of innovations to the table that set it apart from its peers.

They sure make them like they used to

The classic tower defence formula is barely touched mechanics-wise: place a few turrets of varying strength and effects along a road that periodically fills with waves of miscreants.

A few new gameplay additions, like acquiring Hero units that boost your power-ups and chasing stolen crystals, serve to freshen things up in some respect.

But while it doesn’t completely rework the successful formula, Tower Raiders 2 does manage to nail a lot of the basics that its TD competitors often overlook.

Fight fire with tsunamis

Concepts such as maximizing the amount of firepower in one spot by clever placement and upgrading of turrets can be disregarded in, for example, Fieldrunners - if things get too rough, you can just place more turrets to get on top of things again.

Here, careful management is a necessity: placing the wrong kind of turret or spamming them, instead of upgrading what you already have, will quickly result in a character-building defeat.

The remarkable thing is that being beaten by the AI never feels undeserved. The free-form level design leaves ample room for the computer opponent to outmanoeuvre you, and it usually will given half a chance.

Visually, Tower Raiders 2 only displays the bare essentials, but the satisfying mechanics and quirky humour make this no-frills tower defence game easy to recommend.