Thel 'Vadam, also referred to as the Arbiter, is the deuteragonist of Halo 2, a protagonist in Halo 3, and the most prominent Sangheili shown throughout those games.
Powers and Stats
Tier: 9-B to 9-A with physical blows, likely High 8-C with direct impact; at least 9-C to 8-C with most weapons; High 8-C to 8-B with heavy weapons
Name: Thel 'Vadam(ee), "The Arbiter"
Classification: Sangheili Arbiter
Powers and Abilities: Superhuman strength, speed, durability, agility, stamina and pain tolerance, extremely skilled and experienced combatant, master of armed and unarmed CQC, can quickly master the use of virtually all manner of weaponry, excellent military tactician
Attack Potency: Likely Wall level to Small Building level with physical blows, likely Large Building level with direct impact (comparable to SPARTAN-IIs like Master Chief); At least Street level to Small Building level+ with most weapons; Building level to City Block level with various heavy weapons and demolition explosives
Speed: Superhuman+ travel speed (comparable to SPARTANs like Master Chief); Subsonic combat speed at least Subsonic+ reactions (can contend with SPARTANs in close combat), likely Supersonic+ reactions (Should be comparable to Master Chief and other Spartans)
Lifting Strength: Superhuman
Stamina: Superhuman+ (Comparable to Spartans and superior to any normal, unaugmented humans)
Range: Extended melee range, up to several hundred meters with ranged weapons
Intelligence: Excellent military tactician, skilled with almost any weapon and vehicle
Weaknesses: Can go into a frenzy if angered