This card works well against the milling mechanism of the LIGHTAttribute "Lightsworns" as they will keep on sending cards, possibly copies of themselves, from the Deck to the Graveyard, thus increases this card's ATK.
If your opponent has a LIGHT Deck, you could use "Vampire Lord" and every time it inflicts battle damage choose monster thus they will keep sending (hopefully) LIGHT monsters to the grave to boost this card.
It should also be noted that this monster is Level 8, which is considered to be the easiest Level of Synchro Monster to Synchro Summon. Just like "Stardust Dragon", this card can be Special Summoned in one turn by Special Summoning a Level 5 non-Tuner (such as "The Tricky" or "Cyber Dragon") and then Normal Summoning a Level 3 Tuner (such as "Junk Synchron" or "Psychic Commander").
Be careful when fighting against LIGHT Deck like "Lightsworns", as "Honest" could turn things around in your opponent's favor. Keep a card like "Divine Wrath" or "Chivalry" handy before you battle with this card.
When against "Lightsworns", "Light Of Destruction" will not only help them mill out faster, but will possibly also give "Light Gazer" an ATK boost.
This card can be used to counter "Herald of Perfection" Decks (as long as "Archlord Kristya" is not present on the field first) since the ATK of "Light Gazer" can easily surpass the DEF of "Herald of Perfection". Also, since this cards effect is continuous, "Herald of Perfection" cannot negate it.