What does "playing back no sums" mean in League of Legends chat?

Q: What does "playing back no sums" mean in League of Legends chat?

It means "I'm backing off, I have no summoner spells.". "no sums" means no Flash and no Teleport. Without them, being ganked is a guaranteed death: playing back is not fear, it is arithmetic. The jungler knows not to count on that lane for a few minutes.

team chat

what you want to say

I'm backing off, I have no summoner spells.

what you type

playing back no sums

the context

Explaining a passive laning phase to the jungler.

What it actually means

"no sums" means no Flash and no Teleport. Without them, being ganked is a guaranteed death: playing back is not fear, it is arithmetic. The jungler knows not to count on that lane for a few minutes.

Related lines

hard matchup playing under towerIt's a hard matchup, I'll play under tower.
flash up 30sMy flash is up in thirty seconds.