Metroid Dread now offers three boss rush modes, thanks to today's free game update. You'll gain access to the first after completing the main game's story.
The standard Boss Rush lets you fight 12 bosses one after the other, with damage from each carried over to the next. Weapons are fully restored, however.
Your aim here (apart from at the boss' weakpoints!) is to down each boss as quick as possible. If Samus is downed herself then you'll be able retry your current boss fight, but incur a time penalty.
Complete Boss Rush and you'll unlock Survival Rush. This gives you a five-minute time limit to defeat as many of the game's bosses as possible. Here, one defeat will mean game over. However, each successful defeat of a boss will add time back to your clock.
Finally, there's Dread Rush. You'll only get access to this if you beat the main game on its one-hit-kill Dread Mode. Here, any damage from a boss will mean an instant game over. Good grief!
Not played Metroid Dread yet? It comes well recommended. "A stylish, visually sumptuous return for 2D Metroid, and an adventure that proudly sits alongside the series' best," Martin wrote in Eurogamer's Metroid Dread review, awarding it an Essential rating.