Hobgoblin Warrior

Hobgoblins as allies happen most often through a treaty, a shared enemy, or a contract. The framings that hold up: a Lawful Evil legion has agreed to flank the orcs alongside the party for one battle, a hobgoblin sergeant owes the paladin a life-debt and has loaned a squad as bodyguards, or the party is undercover with the legion and these warriors believe they outrank them. The alliance is bureaucratic, not friendly.

Run the squad as professional auxiliaries. They follow orders from a named officer, ideally an NPC the party negotiated with, and they will execute any tactical command that fits the contract. Pack Tactics works regardless of whose side they are on, so position them in pairs flanking the enemy front line and direct longbow fire at the highest-priority target the party calls out. They average 24 damage in a round on Advantaged attacks; that is enough to drop a CR 2 ogre in two rounds with a four-warrior squad.

What they refuse: any order that breaks the agreed terms, any insult to their chain of command, any task involving prisoners that the contract did not specifically cover. They will not improvise, they will not "save" a PC who runs into a stupid position, and they will not stay one minute past the agreed campaign. If the party tries to extend the deal mid-fight, the senior warrior pulls the squad off the line and waits for new orders.

Pay them in coin, weapons, or land grants. Pay them on time. They keep ledgers.

Have the senior warrior salute the party's leader once, formally, before the first fight. The salute is the contract made flesh. Anything that breaks the salute breaks the alliance.

A hobgoblin warrior is a soldier, not a thug. Run them like a disciplined infantry line and the encounter punches well above CR 1/2. The trait that does the work is Pack Tactics: any attack roll the hobgoblin makes against a target with a friendly hobgoblin within 5 feet is at Advantage. That changes a +3 to-hit longsword from a coin flip into a real threat, and Half Plate plus Shield gives them AC 18, which is the AC of an ogre at five times the XP. A four-hobgoblin squad is a meat grinder for a level-2 party.

Open at range. The longbow has 150/600 ft. range and deals 5 piercing plus 7 poison on a hit, so two hobgoblins in cover at 100 ft. can soften a caster before the fighter closes. Once the party engages, switch to longswords (12 average per hit, 2d10 because of the SRD's two-handed treatment). Pair them up, always. A lone hobgoblin loses Pack Tactics and becomes a 11-HP body with a +3 sword. A pair is double Advantage and 24 average damage per round if both hit.

Positioning is the whole game. Use a tight formation: shields locked, bowmen behind, captains calling targets in Common so the players hear the orders. Have the hobgoblins focus-fire one PC at a time. Two hobgoblins with Advantage on the wizard will drop the wizard. Spread fire is wasted on AC 18 enemies whose attack bonus is only +3.

These are soldiers with a chain of command. Once the squad leader falls and they are below half strength, they fall back in good order. They do not rout. They retreat to a defensible position, blow a horn, and the next encounter is bigger.

Have one hobgoblin shout a target in Common before each volley. "The one with the stick." "The one in the robe." The party should know they are being hunted by a plan, not by hatred.