These days, some wizards are finding that they have a little too much spell left at the end of their mana.

Nether Void

Whenever a player casts a spell, counter it unless that player pays {3}.

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Masters Edition III

Whenever a player plays a spell, counter it unless its controller pays {3}.

Legends

All spells cast are countered unless their casters pay an additional o3.

This is not an additional cost, it is a triggered ability.

This has the supertype world. When a world permanent enters, any world permanents that were already on the battlefield are put into their owners' graveyards. This is a state-based action called the "world rule." The new world permanent stays on the battlefield. If two world permanents enter at the same time, they're both put into their owners' graveyards.

The ability triggers whenever any player (including you) casts a spell of any type.