Tundra Warrior:
Bertryll's time as a cossack has taught him the secrets to survival in the wilderness. His experience living off the land throughout the Great Grass Sea, Galena Veil, and Galena Mountains have made him a master of nomadic travel. As such, Bertryll can always remember a region's geographical features and can find enough food and water for six people. His experience has made him unparalleled in both travel and survival in the tundra. He has advantage on WIS and INT checks in the tundra, and receives bonuses traveling through this terrain. He also has survival and INT checks concerning abberations, and knows void speech.

Master of the Steppes - Ranger - Cossack :
An unparalleled mounted combatant, Bertryll's service as a cossack with the Royal Army showed him the importance of the horse being an extension of the man in battle. While mounted, he gains advantage on attack rolls against creatures smaller than his mounted, can force an attack on his horse to target him instead, and if his horse is subjected to an effect forcing a dexterity saving throw to take half damage, it instead will take no damage on a successful save and half if failed.

New Era of Warfare - Fighter - Gunslinger :

Bertryll has a passion for ranged weapons and its improvement, inventing black powder firearms inspired by the weapons he saw in the Astral Plane. He has learned how to make his shots count in a bonus action while making a firearm attack by aiming and bracing the weapon to gain advantage. The weapon will misfire and temporarily be unusable until repaired at short or long rest in the event of a 1 or 2 on a d20.

Armor and Clothing: Scale Armor, Set of traveler's clothes

Weaponry: Blunderbuss, Halberd, Handaxe

Equipment: Explorer's pack, staff, hunting trap, belt pouch, balalaika

Valuables: House Starosta Signet Ring

I am a strong silent type unless the topic is weapons – then I gush for hours

Glory. I must earn glory in battle, for myself and House Starosta.

I'll never forget the crushing defeat my cossack host suffered, or the Warlock Knights who dealt it.

The monstrous atrocities of the Warlock Knights that we faced during the Palischuk Schism can't leave my mind.