Troll

Dark vision 60 ft   Regeneration: High trolls heal very fast but not as absurdly fast as their giant counterpart. When they drop to 0 HP they automatically stabilize and when they spend HD they heal double the amount rolled.   You can use you action to spend a single hit dice and regain the HP immediately (doubled by the previous ability, of course). once you use this feature, you can't use it again until you take a long rest   Trained to create and destroy: choose any artisan tool and any martial weapon: gain proficiency in them.   Master of portals: when you make an arcana (intelligence) check to analyse a portal or a naturally occuring weakness between the planes, you are considered proficient in arcana and add double your proficiency bonus.

Languages. Common, High troll