Whenever Dowsing Device or another artifact enters the battlefield under your control, up to one target creature you control gets +1/+0 and gains haste (This creature can attack, and as soon as it comes under your control.) until end of turn. Then transform Dowsing Device if you control four or more artifacts.

(Transforms from Dowsing Device.) : Add . , : Until end of turn, target creature gains haste (This creature can attack, and as soon as it comes under your control.) and gets +X/+0, where X is the number of artifacts you control. Activate only as a sorcery.