Dean Vellio is one of the people who requires escorting in Temple Trekking. Dean resembles players in many aspects, mainly through his choice in armour and his seeming access to the slayer skill. Dean is one of, if not, the strongest follower in Temple Trekking. He is an Easy tier follower and has a higher defence and strength than the other followers.
Despite only gaining a +1 attack speed at level 75, Dean already attacks 1 tick faster with the dragon longsword at 4 ticks (speed of scimitars) at level 1, and instead fails to gain the additional attack speed on top of this when he does achieve level 75. It is unknown whether this is intentional or a glitch.
After the March 2012 graphical update the Bandos chestplate's graphics were updated, but Dean's armour wasn't changed accordingly until the June 2012 Crucible Update.