Fight
LMB shoot · RMB aim / scope
1–5 weapons or wheel · F pickaxe
R reload · E open chest / pick up gun or med kit · X drop weapon
H hold to use a med kit — heals over a few seconds, stand still
MMB ping (again on it to clear) · click the map to ping, right-click to clear
Build
Q toggle build mode · wheel cycles wall/floor/ramp/cone
LMB place · 10 wood per piece · pickaxe trees & rocks for more