This card can easily destroy "Light and Darkness Dragon". If "LaDD" is attacked by it and activate its effect to negate its own attack, "LaDD" will be forced to negate your effect, and have only 2300 ATK left, which is enough to destroy it by battle.
After this card has no Xyz Materials attached, equip it with "Axe of Fools" to negate the second negative effect and give it 1000 ATK.
Negate your own attack using its effect then use "Double or Nothing!" to enable one of your monsters to attack with twice the power instead.
In fact, if this card negates two attacks from one of your own monster, two "Double or Nothings" can be used in a Chain and if the target monster has at least 2000 ATK, an OTK can be achieved.
This card's effect can also be used to negate its own attack, then use "Double or Nothing!" on it, attack again, then negate the attack again before using another "Double or Nothing!" on it. As "Utopia" itself has 2500 ATK, this should give yourself a 10,000 ATK "Utopia", enough for an OTK.
This card's effect can be used to prevent your monsters from being forced to attack.
Because this card is a LIGHTAttribute monster, "Honest" can be used if your opponent attacks it with a stronger monster, preventing yourself from wasting the Xyz Materials when using its own effect.
When this card runs out of Xyz Materials, Tribute it to Special Summon "Turret Warrior" before it destroys itself, or use it to Xyz Summon "Number C39: Utopia Ray"; even if there is no ATK or DEF change, at least it won't destroy itself.
"Number S39: Utopia the Lightning" can also be Xyz Summoned this way to stop the card's negative effect, or it can be Xyz Summoned while Number 39 still has at least 1 Xyz Material to use its 5000 ATK effect.
Use a monster that must be targeted for attacks to stall for when this card is out of Xyz Materials, or use two to shut the attacks down completely.
"Scarred Warrior" is a particularly good option, protecting "Utopia" from attacks (and by extent, its self-destruction effect), a decent enough 2100 ATK, and inability to die once per turn makes a good combo for preserving this card's Xyz Materials.
Use "Overlay Regen" with this card to block three attacks instead of two.
"Number 19: Freezadon" can further supplement "Utopia" by using its Xyz Materials via its effect along with "Utopia's", granting up to four negated attacks. Combine with the above strategy and "Utopia" will basically have five Xyz Materials at its disposal.