How about some Draining cards?

[NeoRWBY65]

Draining Field Generator Mk. 1

Spell/Continuous

During each of your end phases, put 1 counter on this card. Monsters on your opponent's side of the field with less than 1000 DEF lose 100 ATK and DEF for each counter on this card.

 

Draining Field Generator Mk. 2

Spell/Continuous

If "Draining Field Generator Mk. 1" is not on the field, destroy this card. During each of your end phases, put 1 counter on this card. Monsters on your opponent's side of the field with less than 2000 DEF lose 200 ATK and DEF for each counter on this card.

 

Draining Field Generator Mk. 3

Spell/Continuous

If "Draining Field Generator Mk. 2" is not on the field, destroy this card. During each of your end phases, put 1 counter on this card. Monsters on your opponent's side of the field with less than 3000 DEF lose 300 ATK and DEF for each counter on this card. Your opponent cannot target any spell card you control with a card effect.

[newhat]

Mark 1 is slow but reasonable. It's absurd to decrease the ATK and DEF of opposing monsters with 3 Continuous Spell Cards that can all be taken out with a single Mystical Space Typhoon. Add some incentive to use all three cards.

[NeoRWBY65]

Mark 1 is slow but reasonable. It's absurd to decrease the ATK and DEF of opposing monsters with 3 Continuous Spell Cards that can all be taken out with a single Mystical Space Typhoon. Add some incentive to use all three cards.

is that better?

[newhat]

That's slightly better, but still very situational.

[Sleepy]

What about, if one of them is destroyed, they all lose their counters instead? I mean, it'd be better than self-destroying, and it'd still auto-disrupt their strategy, but to a more reasonable degree, because I understand that the need for a drawback comes from the Counters stacking the effects every turn.