Stolen Stark Tech

Flash on an Equipment collapses two spells into one: a combat trick you can hold up like an instant, and a permanent buff you keep once the ambush resolves. The self-attach clause on entry is the mechanism that makes the flash worth anything; without it, you would be flashing in an artifact that just sits there. Drop it as the opponent points removal at a creature or declares an unfavorable block, and that creature keeps the indestructible, the +1/+0, and the Equipment, so a bait trade becomes a two-for-one with a residual body upgrade attached. The restraint lives in the wording. The indestructible expires at cleanup, so you are buying a single surprise turn rather than a standing shield, and after that first flash the equip cost is sorcery-speed like any other piece of gear. Two mana buys the ambush, not lasting protection: once the turn resolves you are left with an ordinary cheap Equipment that nudges power up by one. That divide between the front-loaded trick and the modest permanent it leaves behind is where the card is priced. It belongs to the family of instant-speed protection effects that reward keeping mana open and reading an opponent's line, but it banks its payoff as a permanent instead of spending it on a one-shot spell, which is the trade the design leans on to stay fair.