The leader of the Kalphite race is a significant adversary
Then there are Quest Bosses OSRS gold for sale which are met during various adventures set by NPC's. This is undoubtedly the biggest group in this conflation that includes diverse creatures, ranging from animal-like through humanoid, to normal monsters.
They range in strength and range from bosses to be confronted in the early game, and the most lethal threats to the endgame. They all are...