The Sentinel just looks like A Robot being controlled by a human *which explains it can bleed*. This hero is the only one who is equipped with shields *except the Riot SWAT*, however his shields have a direct health of 150 and can regain if not attacked for a while. This hero can be bought from the store/shop in the 'HEROES' section
The Sentinel Makes a Barrier in front of himself that makes through the whole map. It blocks the slasher, while lets the survivors and himself pass through. This ability has a set duration of 15 seconds and a minute's cool down. The Barrier duration or cool down can be increased based on his skin, which excepts Cyan, pink, red, blue, green, default, silver, golden or exclusive skins.
The Effective skins are - Night fall skin - +50 health, -50 stamina, -30 sec cool down -10 barrier duration
Shepard Skin - (idk health, sorry :/ , its been a while) -50 stamina, +1 speed, +20 sec cool down +5 barrier duration