Covenant Seraph-class starfighter
From Halopedia, the Halo wiki
The Seraph-class starfighter is the Covenant Starfleet's main starfighter, and are hypothesized to be the Covenant's counterpart to the U.N.S.C. C709 Longsword starfighter. They are teardrop and piscine in form.
Appearances
Although Seraphs are often mentioned in the novels, the only occasions a Seraph fighter is seen well in the games is in Halo 2, on the levels The Arbiter and The Oracle, where one is seen in a hangar in a Forerunner facility in Threshold, which the Covenant storms in an attack on the Heretics. The Heretic Leader attempts to escape the storm on Threshold in the Seraph, but is successfully stopped by the Arbiter, who slays him in combat.
Two Seraphs can also be seen at the end of Cairo Station in the cinematic scene where Master Chief is about to return the Covenant's bomb, but they speed by fast, so you can't really get a good look at them then.