- Attack him with a stronger monster (Honest works well here. Note that Honest does not target Obelisk)
- Take control of him with Creature Swap (Does not target)
- Destroy him with other non-targeting effects. Smashing Ground, Fissure, Torrential Tribute (can't be used against Obelisk's own summon), Mirror Force, Ally of Justice Catastor, etc.
- Deal with him with other non-targeting effects, ie, bounce him to hand with Grand Mole or Legendary Jujitsu Master, or remove him from play with DD Warrior Lady, etc.
- If he tries to use his Ignition Effect, you can use Divine Wrath.
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