Playing as Reaper
Becareful, Reaper's teleport ability is not a good tool to enter a fight. While using it you will be vulnerable at departure and arrival for 2 seconds. Be sure to teleport to a location where no enemy can see you, especially snipers as they love easy pick offs
Always be flanking. Let the rest of your team take the typical route while you move down the road less travelled, disrupting and generally frustrating the enemy. Don't give them space to breathe for a minute.
Using Melee attack animation cancels your reload, allowing you to complete your reload, and begin firing again, almost instantly (and while doing a bit of melee damage in the meantime)
The casting of Shadow Step is pretty apparent to any nearby enemies, so only use it to either escape or head to a position that you feel absolutely sure is safe. Be ready to start firing when you drop out of this mode.
On maps with lots of elevation change, try to channel your teleport to above the enemy team or into the side portion of doorways so that they're unable to see exactly where you're teleporting to.
A particular powerful combo involves using Shadow Step to get close to the enemy, then dropping Death Blossom onto your fresh batch of victims.
You can use Reaper's mobility Abilities to get behind tanks and turrets and pick them to pieces while their shields point uselessly ahead of them.
Reaper isn't actually invisible when he uses his Wraith Form. I've overheard on streams that people believe they're "stealthed" whenever they use his Wraith form, but it's primarily used as a tool to escape players when you're in danger, to reposition yourself in close-quarters to secure kills on targets that are foolish enough to follow you.
Try to get a vantage point before using your ult. Jumping in the melee from above while using it is deadly.
whilst playing as reaper you want to use your wraith and shadow step to you most use use shadow step and get in close use wraith to evade enemy contact
Playing with Reaper
While using his ultimate (Death Blossom) he is actually really vulnerable to controls, and snipers. Try to protect him for maximum efficiency
Try to keep the snipers busy while he his moving on the open. He will thanks you later.
Playing against Reaper
If you see his discarded pistols on the floor, watch out! The game stores a handful of these at any one time, and he may well be close by with a fresh round of ammunition, just waiting to be unloaded into your face.
Reaper is only deadly at close range, try to keep him at least at mid range and you will be fine.
Reaper is able to teleport from long distances, so keep a look out for his red smoke before he emerges to sneak upon you and your team.