Odd Engineers are shown to be heavily deformed, and usually have flipper like hands. They can also change their body.
Odd Engineers often attack mercs in packs, or by themselves. They cower in fear when they are in danger.
Odd Engies are capable of wall-crawling, which they often use to ambush unsuspecting victims. Most Odd Engies possess increased durability. Some of them exhibit inhuman strength as well, and are capable of neck-lifting humans with little effort.