Interdimensional Web Watch

Impulse-draw effects usually hand you cards for free and then dare you to cast them before the window slams shut; the friction lives in the mana, since you often tapped out just to deploy the digging in the first place. This design pairs the two halves and keeps them apart in a useful way. The enters trigger exiles the top two cards with a play-window that stretches through your next turn, the familiar impulse half. But the artifact does not leave once it has done that: it stays on the battlefield as a permanent mana rock, and its tap ability produces two mana of any colors, spendable on any spell cast from exile. That last clause is broader than it first reads. The mana is not welded to the two cards it just showed you; it funds anything you are casting from exile, so it pays for foretold cards, the creature half of an Adventure card, a cascade hit, or the spoils of any other impulse effect on the board. Restricting the rock to exile-casting narrows it away from generic ramp: you cannot accelerate your hand with it, only your exile pile. The result rewards building around exile-casting rather than a one-shot rummaging trinket, and the two-turn window on its own trigger gives you room to untap, find the colored mana you were missing, and cash a spell that would otherwise have expired uncast.