Another word for a game mode: Endless

I am currently developing an Android game that will have two mods: Timed and Endless.

In Timed mode you have 1 minute to complete as much items as you can. In Endless mode, you have 5 seconds to complete an item, but as long as you can keep up the game never ends.

Is the word Endless correct to describe this method? What would be a better one?

EDIT: I'd like to thank you all for your answers and opinions; as some of you have noted there is no one correct answer, but a choice of mine. I'm walking away with a lot of good options on my hand thanks to you.

Endless mode is commonly used in video games, and so is survival mode, which sounds a bit more exciting – how long can you last? Infinite is also sometimes used.

Of course, you can call it what you like. There's no single correct answer. You could even make up a new name like panic mode if it fit the atmosphere of your game. A more restrained suggestion like untimed might work best if it's a relaxed game with no pressure – play as long as you like, it's untimed!

So really, it's up to you as a game designer to pick the term that fits your game best. That said, my personal favorites are survival and endless. I usually end up using one of those two terms when I'm talking to my friends, no matter what the author of the game chose to call it.

Coming from a game lexicon point of view, there's a common term that is applied to games like this - "Endurance Mode".

Games in Endurance Mode are testing just that - your Endurance. Typically you're given the ability to build your 'character' or 'building' or whatever you happen to be using in the game up to its peak performance, and are then given an endless stream of challenges, to see how long you can last in that mode.

Some games that use this terminology are Dominion Tower and Rise of the Tomb Raider.

A perpetual mode, perhaps!

2. Occurring repeatedly; so frequent as to seem endless and uninterrupted

[ODO]

Depending on the kind of game, it could be called Arcade-Mode.

Especially what you are describing actually IS an arcade mode.

An arcade game is known for its increasing difficulty, while you just have short time to get the next checkpoint giving you some additional time.

But they are never "endless"¹, even more they are pretty shortlived. So the terms are not synonym, although in theory the arcademode could be played endless.

¹_{endless-mode would let me first think of something like simcity in a mode without any dangers}