Now you see me... now you don't

To a Stalker, almost all encounters are optional.

The Stalker is the stealth class of City of Heroes, and does what you'd expect a stealth class to do – running around hidden until they reveal themselves with a high-crit opening attack. However, CoH takes this core ability and ramps it up to 11.

Hide is the first power obtained in a Stalker's secondary powerset regardless of which set has been chosen. It provides a small defense bonus but it's primary function is as a stealth power. Unlike similar abilities in some other MMOs, Hide stays active indefinitely – even after broken by an attack, a Stalker will automatically go back into Hide if out of combat for more than ten seconds or so – and it renders the Stalker completely undetectable by almost every enemy in the game, and at any range. Seriously, you can stand in front of an enemy mob 40 levels higher than you and they won't see you. I once toured Grandville, the 40-50 zone on Redside, on a level 15-ish Stalker. No aggro.

(Well, almost no aggro. There are a handful of enemies that can see through Hide, but these are very rare.)

This creates some interesting opportunities as well as raising some questions – the big one being why Stalkers don't just ghost through every mission in the game. After all, if your objective is to defeat the boss at the end of the map, why fight your way through all the mobs in between you and your target when you can just walk past them?

You could, but it's not that simple. Interacting with an object takes you out of stealth so if there's any mobs in the vicinity of an objective – and there usually is – then you'll have to take them down. Similarly, NPCs in escort missions are as unable to see through Hide as anyone else, meaning you have to drop it or they won't follow you; that can get messy if you didn't clear your escape route on the way in. Likewise, some ambushes will home in on you, stealthed or not. Finally, you can't ghost a 'Defeat All' mission.

All of these are mission-specific situations where Hide is of limited use, but there are other more general reasons not to ghost everything in sight. In CoH the majority of your XP comes from defeating enemies, and whilst some missions do give a big XP reward upon completion, if you're not fighting most of the enemies you encounter then you're going to blaze through the missions fast but not have much to show for it. This raises the risk that when you do come up to an unavoidable encounter you might be underleveled for it – especially early on when you're still building up your powers – and that can hurt. I was only level 9 when I hit the last mission of the 1-10 arcs in Nova Praetoria, and in the triple (!!!) boss fight that ends the final arc I was definitely feeling the lack of my level 10 power.

Besides that, ghosting everything is boring. Fighting stuff is one of the best parts of City of Heroes. Why would you not want to fight stuff?

I've yet to use Hide to outright avoid an encounter inside a mission, but I have used it to give me more control over the order in which I take on certain enemies – e.g. sneaking past a boss with a +1 level advantage over me because I was half a bar of XP away from levelling up, then coming back to take them on after I'd actually levelled up on mobs elsewhere on the map.

I have used Hide extensively in the zones though, and in a break from my usual habit I've barely fought any mobs on the streets of Nova Praetoria. Not for nothing is Hide sometimes referred to as the best travel power in the game.