Playing as SCP-106 guide:

Honestly I feel like 106 is severely underrated as an SCP, he has so much more potential to him that people actually show and he's made out to be one of the worst SCPs there is when he has such unique aspects others don't have.

First let's talk about his sinkholes, understandably sinkholes cover a lot of makes 106 what he is, take them away and he loses a lot of purpose and effectiveness. Sinkholes allow 106 to complete avoid his weaknesses and situations he can't handle, as well as weaknesses for SCPs as a whole. Being naded in an elevator, being Micro'd, can all be stopped entirely by a good enough reaction time and proper usage of his sinkholes. Sinkholes can do much more though, rapid coverage of the facility is outstandingly effective, the ability to supposedly get from Point A to B at will in a matter of seconds and deciding where exactly you leave point B sounds great on paper and ingame. One thing I'd like to state first right now, do NOT leave your sinkhole at your containment chamber to try catch people femur breaking you. People don't escape the Pocket Dimension outside your chamber anymore, hell they won't even be in Heavy if they weren't there prior. Leaving your sinkhole there at all times is completely handicapping 106 and doesn't let him use his main ability. Use sinkholes effectively by leaving them at escape routes your targets plan to go to like around the EZ checkpoint, the other side of elevator systems and such, but do make sure your sinkhole is placed conveniently at the location, placing a sinkhole between the 2 elevators at an elevator system still lets people get past you, whereas placing them in a thinner part of the corridor warrants you effective cutting off the path entirely since the enemy would have to run through you, to which you'd grab them. Personally I'd recommend leaving a sinkhole on the opposite side of an elevator system when going into LCZ and "accidentally" leaving an elevator waiting for the human classes so they'd try go for it and be baited and let their guard down. Once in Heavy, I'd place it a hallway or two down from the EZ checkpoint so that I could cut off people that escaped my grasp beforehand, note I specified 1-2 hallways down, this is so that I have a much larger time window to use it if I see my target going through the checkpoint, and allows me to sinkhole to the location if I even just HEAR the checkpoint alarm. For gates to surface when wave spawns become a problem, I'd recommend leaving a sinkhole at the elevator in EZ's side, this way you can try and grab people on surface and use it as either a cut-off point for people using the elevator to escape you, or if you need to retreat, you basically have a portable elevator system only you can use to quickly get out. Once you've done so, enemies would think you're particularly vulnerable and let their guard down and attempt to enter the facility, to which they'd run into you. 106 does suffer a bit in large groups shooting at him, but a large group in an elevator is just free kills.

Now let's look at the pocket dimension, something that has always been argued to be a "weakness" for 106, but in actuality can be used as a great strength. Let's put it like this. Let's say an enemy makes a strong item at 914 or such, if another SCP kills said enemy, the item is still on the ground ready for the taking. If the enemy got to HCZ with this item, it would end up in HCZ when they died, which could be even worse, I imagine you're seeing the point here. 106 grabbing people and giving them a 25% to escape alive could be debatably seen as a weakness, but the pocket dimension is essentially an SCP safehouse for the items on the map. Once you grab the person with Micro, the Micro is now in the pocket dimension, it being much less of a threat to all SCPs and unlikely to ever show up again. People do have a bit of time to grab items usually, but don't because they are in a panic and don't want the pocket dimension to take a toll on their health. The fact of the matter is, a 25% escape chance is more powerful than people even realise, 939 2-taps people on full hp 100% of the time, whereas 106 only has a 25% chance to and a 75% to 1-tap, which would turn into a 6.25% to 3-tap and you get the idea. Once you as 106 have succesfully made sure no good keycards are still on the map to contain you, you have essentially removed most of your weakness and become much stronger.

One thing I hear people say is that 106 supposedly becomes "stronger" if the nuke detonates since he just 1-tap kills like 049. This is definitely not true, while it may seem like that's a buff, you have to remember 106 is slower than human classes and surface is extremely spacious, with minimal opportunities for SCPs to get the jump on people.

Things to grab from this are:
Prioritise LCZ and civilian classes wherever you can
Use sinkholes properly as said above
Try and prevent the nuke from being turned on
Don't forget you're the 1 SCP who bypasses doors, if an SCP is waiting for people to come out of 914, just tell them to go find others while you deal with the matter
This isn't stated in the guide, but be VERY weary of people you chase through tesla gates if they appear to hold a light bulb, they will likely try to manual trigger the tesla to tank some of your HP off
As 106 you should literally NEVER be dying to decontamination or a fog jar, these are already pretty easy to avoid, but as 106 there is no excuse
You can tank the most bullet damage, your HP amount and bullet efficacy let you take around 2.5x as much damage as 049