Data Blast is a breaker program which breaks 1 firewall on all mainframe devices in a radius of 5 tiles, for a cost of 3 PWR. It has no cooldown. Data Blast can be bought from some Server Terminals for 400 credits.
Data Blast's radius must be centered on a tile within the facility's boundary which has been revealed, either by exploration or for any other reason, and it only breaks firewalls of devices on revealed tiles. Devices on unrevealed tiles are not affected even if they are within Data Blast's range.
Data Blast's PWR cost per firewall hacked compares favourably with other instant breakers without cooldowns. It is most efficient when there are many devices you want to hack within the same 5-tile radius, but even when you only hit two devices with Data Blast, its PWR efficiency is better than Lockpick's. Data Blast is therefore considered to be quite a good program.
However, Data Blast is usually not flexible enough to meet all of your hacking needs. It is least efficient when you need to hack just one device with many firewalls, so you will usually want to pair it with another breaker better-suited for that purpose such as Dagger, Hammer, Parasite or Wrench, or perhaps Buster Chips. Data Blast's usefulness is also lower in the OMNI Mainframe mission where devices have higher firewalls and are more spread out, so it is less common to hit multiple devices in the same 5-tile radius.
It is usually possible to position Data Blast's radius to miss devices with daemons, though this may mean missing other devices too. In rare situations there may be no way to avoid hitting a daemon on a device you don't want to hack, so you must either use a different breaker on the device you want to hack, or trigger the daemon.
Occasionally, there are devices which would fit in a 5-tile radius, but you cannot hack them together with Data Blast because it can only be centered on a revealed tile. In this case, you may be able to reveal the tile first (e.g. by peeking), but only if it is within the facility's boundary.
Data Blast hits devices on revealed tiles even if the device itself is not revealed, so it is sometimes possible to hit drones you can't see (or any guards with firewalls). If you do hit one, its location will be revealed in Incognita view, and you can continue hacking it with other programs:
Clip from AndrewKay.