Multiplayer Shootout is broken in 4.12. Appears to be caused by the AimOffset animations being imported at the incorrect scale.
Regression: Yes, does not occur if you create a 4.11 version of the project
1. Create a 4.12 Multiplayer Shootout project
3. Draw your weapon with Right Click
Result: Character shrinks and if you try to shoot, you teleport across the map
Expected: Character draws his weapon
Head over to the existing Questions & Answers thread and let us know what's up.