Barbarian Slingers - Good description, nothing wrong here that I can find.
Celtic Light Spearmen - Description refers to the CLS as "Warband". Other than that, no issues, with the exception that it seems a tad short.
Celtic Light Cavalry - Description refers to CLC as "celtic Light Cavalry" (at start of the sentence). Again, no issues other than that.
Getic Archer - Description refers to a Getic cavalry unit, instead of archers.
Boii Infantry - Description seems to be referring to a Belgae Heavy Spearmen unit.
Boii Hvy Swordsmen - Unit name uses the abbreviation of heavy when refering to the unit ("hvy"). Description refers to, again, a unit of the Belgae.
Boii Elite Skirmisher - Description is that of a Barbarian Warlord.
Celtic Medium Cavalry - Description is good, but specifically mentions that the CMC are Avernian.
Barbarian Chieftain Cavalry - Description is good.
Barbarian Peltast - Description is good.
Celtic Longshield Skirmisher - Description makes little sense. It refers to Ariovistus and Caesar's diplomatic contact, only seeming to mention the unit itself with the first sentence: "THis unit has [a] wide recruitment area due to its hardy nature and disciplined fighting style."
Celtic Light Swordsman - Description is that of a Heavy Swordsmen unit, not a Light unit. Also, unit name should be "Celtic Light SwordsMEN", right? I assume we are recruiting more than one guy here

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Celtic Warband Archer - Description is good.
Insubres Infantry - Description seems good, but is that of a Falx unit.
Celtic Chariot - Again, description is of a Barbarian General's unit.