There's a strong chance that Borderlands 4 will feature a playable Siren, and that means that it's worth looking into what their powers could be. As the main supernatural element of the series, as well as a plot-important one, the Sirens are a highly memorable aspect of Borderlands. To date, every main entry in the series has had a playable Siren, and according to tradition, Borderlands 4 has a good chance of featuring one in its cast as well. The big mystery surrounding it would be what powers the next Siren character will end up having.
When it comes to the Sirens of the Borderlands series, there are a couple of notable rules. Only six can exist at one time, each with a unique power. As a result any living Siren's power cannot belong to another. As of Borderlands 3's ending, Tannis has acquired Angel's powerful Phaseshift power, letting her control technology. Amara still has her Phasetrance power, letting her create psychic arms and fists. Finally, after Maya's death, her apprentice Ava inherited Phaselock, letting her freeze and control her enemies. Unless one of these characters dies or is playable in Borderlands 4, that game's Siren will not have one of these abilities.
Borderlands 4's Siren Has a Few Powers To Choose From
The most recently revealed Siren ability, Tyreen's Phaseleech powers from Borderlands 3, could be a good well to draw from. Phaseleech is easily the most stereotypically villainous Siren power, allowing the user to drain energy from others to restore their own, and it can also be used to steal the powers of other Sirens, as shown by Tyreen and Troy stealing Lilith and Maya's Siren abilities during the story. A Phaseleech Siren would probably have skill trees revolving around healing themselves by draining the health of their enemies. It would also be interesting to see what kind of Siren got this ability after Tyreen's death.
At the end of Borderlands 3, it's not clear whether Borderlands' arguable main character Lilith is still alive. That raises the possibility that her Phasewalk ability could be transferred to another Siren. Phasewalk is a simple yet strong ability that lets the user temporarily become invisible and invincible, releasing damaging psychic blasts at the beginning and end of its use, with upgrades that could daze and shock enemies as well. Since Phasewalk was already Lilith's ability in the first Borderlands, it may be unlikely to see it used again. However, a new Siren could feature a new variant of the ability.
There's also the chance of Borderlands 4's playable Siren to have a completely new power. While according to Borderlands' lore regarding Sirens, there can only be six at a time, only five Siren powers have explicitly been revealed. Since the games have already featured several unique ways to manifest the psychic powers of Sirens, it's up to speculation what the next Phase ability could be. It could perhaps be some form of telekinesis, or a new tool to change the flow of combat. With all possibilities considered, unveiling a new Siren ability would probably be the most exciting possibility to take.
The possibilities for Siren powers in Borderlands 4 are incredible, but it will likely be a long time before anything concrete is revealed. If Borderlands 4 has a playable Siren, which seems to be the most likely case, then there are six possibilities for powers at current. Three of them are locked to living characters, one's previous user is dead, one is in limbo, and one is completely unknown. There are a lot of potential powers that a playable Siren could have in a new Borderlands game, but hopefully they will be just as fun to play as past Sirens, no matter what their Phase power is.