Da Costa had led early on through the initial batch of ATTACK MODE activations, with the Porsches running two-by-two and working together for much of the opening half of the encounter under pressure from the Jaguars of Round 9 winner Nick Cassidy and teammate Mitch Evans.
Evans had pushed to the front of the pack on Lap 31 following an interlude from the Porsche Safety Car, but still had one of his two 50kW ATTACK MODE boosts to use in the final stages. The Portuguese in the Porsche was able to break Evans' resistance with a move late on the brakes into the hairpin forcing the New Zealander into outbraking himself wide.
RESULTS: The full SUN Minimeal Berlin E-Prix Round 10 classification
Oliver Rowland then followed da Costa through, with the Nissan driver having clambered from 16th on the grid. The Yorkshireman was unable to apply the pressure as, after Evans took his second 50kW activation, Cassidy battled his way by his teammate into third as the laps ticked down and proceeded to fill Rowlands mirrors.
This allowed da Costa to stride to a second's gap out-front and take the chequered flag for a first win since Cape Town 2023 - an eighth different driver to reach the top step of the podium in Season 10.
Cassidy did make a move on Rowland stick at the last for second and sealed the fastest lap in the process. Rowland would be happy with third given his starting slot, while Porsche could count two cars in the top four with Pascal Wehrlein fighting hard with reigning champion Jake Dennis (Andretti) to fend him off for fourth.
Evans wound up sixth with Jehan Daruvala (Maserati MSG Racing) coming home seventh after picking his way through the field from 13th - a record Formula E finish for the Indian driver.
Taylor Barnard (NEOM McLaren) produced more heroics on his full debut weekend in the series with the 19-year-old stepping in for the injured Sam Bird. He fought from 18th to eighth at the flag.
Joel Eriksson (Envision Racing) secured his best finish with ninth and Jean-Eric Vergne (DS PENSKE) rounded out the podium.
Cassidy leaves Berlin with a monster 45-point haul and the standings lead - 140 points to Wehrlein's 124. Rowland sits third on 118. Jaguar TCS Racing are top of the Teams' running on 237 points with TAG Heuer Porsche second on 183.
Next up, Formula E returns to China and a double-header in Shanghai on 25 & 26 May.
As it happened...
Cassidy jumped Dennis into Turn 1 with Nato following, before Wehrlein was able to fire his Porsche into second come the end of Lap 2.
A tour later and Cassidy decided to take his first of two mandatory 50kW ATTACK MODE power boosts, dropping him to third and promoting Wehrlein to the lead before the rest of the the lead pack made the jump while everyone from P11 to P22 in the second half of the field also took ATTACK.
Lap 4 saw Dennis and Wehrlein follow, though the latter had done enough to retain first position with a 0.5 second gap to Cassidy in second. Porsche elected to have Wehrlein take his second ATTACK MODE boost immediately, leaving him third, just behind Mitch Evans (Jaguar TCS Racing) who'd temporarily taken P1, and Wehrlein's teammate da Costa.
Da Costa made his first trip through the ATTACK MODE activation loop on Lap 8, leaving Wehrlein to take the lead although, again, only for a short spell as the Porsche team swapped their drivers around on track leaving da Costa to attack Jaguar's Cassidy who'd pushed to the head of the pack.
Oliver Rowland was Round 9's ABB Driver of Progress having made the podium from 15th to third, and here, he'd already reached the same spot from 16th on the grid this time around - on Lap 11. Another shunt for Maximilian Guenther (Maserati MSG Racing) left him pointless on home soil and the Safety Car on-track while the pieces were picked up.
On the restart, Lap 15, da Costa and Wehrlein led the pack away in the Porsches, with Evans, Rowland, Cassidy, Dennis, Nato, Mortara, Vergne and Fenestraz the top 10 - all bar Evans had taken both ATTACK MODE activations for the race at this stage.
By the end of that lap, Werhlein led da Costa, with Cassidy creeping inside the latter to take second out of the final turn before jumping for the lead through the first sector of Lap 16; Rowland in the Nissan also jumping da Costa for a provisional third.
Lap 20 and the lead group were running millimetres apart in a constant battle with remaining energy levels looking even - it was anybody's game at just over the half way stage.
Lap 24 and leader da Costa built a second or so as a buffer to Rowland - who jumped by Cassidy and Evans to take second as it stood.
The Safety Car was required again as Nato and Fenestraz came to blows towards the back end of the points-paying positions. The Nissan was left in the wall requiring recovery, while Nato found himself shuffled well down the order.
The race went green once again on Lap 29, with da Costa heading Rowland, Cassidy, Evans, Dennis, Wehrlein, Vergne, Hughes, Daruvala and Barnard. Cassidy managed to squeeze by Rowland into the final sector to take P2 and park himself on the gearbox of da Costa in the lead Porsche. Dennis fell behind Wehrlein in a tense battle for fifth - the latter pushing the former, firm but fair.
Evans gained track position on Lap 31, moving by teammate Cassidy and then leader da Costa though the Kiwi was yet to take his second and final ATTACK MODE boost. Dennis and Wehrlein's scrap continued at the hairpin - the Andretti driver nudging the Porsche, damaging his front wing in the process.
Da Costa broke Evans's resistance at the hairpin, forcing Evans into going in to deep and switching back up the inside for the lead. Rowland took advantage of the concertina to sneak by Cassidy for third in the process, while Taylor Barnard made it by NEOM McLaren teammate Hughes then Andretti's reigning champion Dennis a turn later for sixth - all happening on Lap 35.
Evans emerged fourth after his second ATTACK MODE activation, with da Costa, Rowland and Cassidy ahead on Lap 37. He was able to use that extra 50kW of power to outdrag his teammate into third across the start/finish. Rowland looked immediately under pressure from Evans who had a minute or so of that extra ATTACK MODE power to use. Da Costa out front would have been more than pleased to see that scrap on Lap 38 - leaving the Porsche driver some clear air.
Cassidy made his claim for third with a move up the inside of Evans at Turn 9 on Lap 39, before setting about Rowland and leader da Costa. Into the hairpin, Cassidy made further progress, dispatching Rowland, but da Costa had more than a second in-hand out front. Evans, meanwhile, at the same spot into the final sector was shuffled from fourth to sixth - Wehrlein and Dennis able to profit.
The Portuguese was able to retain that gap to the flag, holding Cassidy at bay for his first win since Cape Town 2023.