Quick answers
How do I use the grappleshot?
Pick it up and press Q (RB/R1 on controller); aim at a surface, enemy or weapon and it pulls you or the item. Check the equipment icon above the shield bar for charges.
What is the melee key in Halo Infinite?
F on keyboard. On controller the Default layout uses the right stick press; the Bumper Jumper and Recon layouts move it to a bumper.
How do I switch grenades?
Press 4 on keyboard or D-pad Left on controller; the icon shows frag, plasma, spike or dynamo.
How do I mark an enemy?
Hold Left Alt (D-pad Up) while looking at them or at a weapon; the mark appears for your team with a distance.
Which controller layout is best?
Bumper Jumper keeps your thumb on the stick by moving jump to LB; many competitive players use it or a custom layout. Test the sticks first in the gamepad tester.
What deadzone should I use in Halo Infinite?
Centre deadzone as low as your sticks allow. Halo ships it high so that no worn controller drifts, which is insurance healthy sticks do not need. Axial deadzone helps on the movement stick and hurts on the look stick.
What is Max Input Threshold in Halo Infinite?
How close to the edge the stick has to get before the game reads maximum. Zero on the movement stick reaches full speed sooner; a higher value on the look stick keeps more travel for aiming instead of spending it on the fastest turn.