Contra 4 arrived on Nintendo DS in 2007, developed by WayForward and published by Konami. It is one of the more successful examples of a studio reviving somebody else's classic series without either embalming it or misunderstanding it.

The structural idea is that the DS has two screens stacked vertically, so the game treats them as a single tall playfield rather than as a screen plus a menu. Enemies fire down at you from the upper half while you deal with things at your feet, and the grappling hook exists precisely so you can launch yourself from one screen to the other. Weapons work on a two-slot system with instant swapping, and picking up a second copy of the same weapon upgrades it. That single rule turns power-ups from a reflex grab into a decision, since you have to consider what you are throwing away.

Difficulty is the point. One hit kills you, but bullets are large and legible and enemy patterns are readable, so deaths feel earned rather than arbitrary. Success comes from memorising layouts and knowing which weapon a section wants. On the standard setting an experienced player will see the ending inside an hour - the game assumes you will go back through it on harder settings, and the design supports that.

The package is generous for a handheld release. A challenge mode breaks the game into short tasks with restrictive rules, and the unlockables include playable conversions of the original NES Contra and Super C, effectively bundling the series' foundation with its sequel.

It has aged very well because it never depended on technology. Sprite art stays sharp, the controls are exact, and the pacing has no filler. The only genuine friction is physical: the plastic gap between the two screens interrupts anything travelling vertically, and no amount of design could fix that.