Omni negation, but there is a cost

[Vlasaras]

when a monster effect or Spell/Trap Card is activated: Negate the activation, and if you do, destroy that card. You must control a face-up attack position level 1 LIGHT monster with 0 ATK to activate and resolve this card.

yea soo, its good...if you are willing to risk it OR be prepared and let that 0 fragile 1 sit there to be ready to counter anything if you are on the offense however its not meant to be used that way..but I believe you thought about doing soo too meh...its not ''casual'' ''casual'' but really it forces you to put level 1 in your deck if you want to even think about it.

[Darj]

Requiring such an specific monster on the board makes it situational. IMO this is on the casual side. It cannot stop Summons so it's not a true omni-counter, and the opponent can Summon anything, battle your monster, then follow up with combos on its MP2. Then again, unless you search this I doubt anyone would suspect you for having this card Set, unless you make the Summon of the LIGHT monster with 0 ATK too obvious. IMO you can get away with making it negate Summons as well. Leaving a Level 1LIGHT monster with 0 ATK on board in Attack Position is enough of a risk and set-up, IMO.