Strategies:-
Leviathans have special shields which allows the Leviathan to be resistant against the type of weapon used. For example, a Laser Shield lessens the damage taken from laser weapons, while Flame Shield lessens the damage taken from flames. It helps to know what kind of weapons your enemies usually use and bring the correct shield. There is another "Shield" that lets the Leviathan be IMMUNE to all sorts of attacks: The Neutron Shield. The Neutron Shield works with its energy. The more you turn it on, the more it drains. Neutron Shields are good for blocking out certain non-blockable damages (eg. Nukes/Impact) for a certain amount of time.

PoC Blocker:-
POC Blocking is pretty useful when there are good defenders, but there is still a chance of Infils being roc-dropped or a mass mob of phasic moths. Take note though that POC Blocking is tough stuff and only experience players should block POCs. Have a good supply of energy (14000-21000). Use H-Dual Methane Extractor or a H-Daniele cell of you have to. You'll need around 8 units to block the POC. Remember to turn on Neutron Shield of you suspect that the nukes are heading your way. Also, make sure that you DO NOT leave Neutron Shield on as it saps energy mighty fast.

*Note* Neutron Shield is an ability, not a shield.