Every time I try and look this up I get hits on how orks conduct their waghs. How do you, that is the Tau/Human/minor xenos prepare your planet/system from initial ork incursions, how you do fight them once they land?

Are there ways to destroy hulks reliably once they pop up in system? On the ground do you fight with concentrated force or use dispersed hit and run attacks? Are Titans better or smaller lighter, vehicles? Best kind of air force mix? How hard is it to get into assassination range of the Warboss? Can you just create a tranq dart and virus bomb chief's in targeted assassinations (I know they used virus bombs tactically on Armageddon)? Can you weaponize the Wagh field against the orks on a large scale? If they are resistant to pain, what about itching powder? Chemicals that smell horrid to Orks?

Can you undercut an invasion by avoiding the Orks themselves and target the Gretchings and Snotlings, thereby forcing the spores to constantly generate them instead of more orks? Mass hypnosis? Getting them to laugh themselves to death? Turning an Ork into a an unmarred Servitor for infiltration with a nuclear bomb in it's gullet?

And if it does come down to conventional arms, what works best on the Orks? Rad guns? Stubbers? Lazguns? The Ninja star rifles of the eldar? Cause I ain't sure but given the nature of nobs, this seems it would be the one time that lazguns are the right choice, but maybe not the best choice.