Clockwork Night

[Toffee.]

Machine-Type monsters you control gain 300 ATK. Once per turn, you can treat all Face-up monsters currently on the field as Machine-Type. Once per turn, you can Target 1 Machine-Type monster you control: It gains 300 ATK for each Face-up Machine-Type monster currently on the field, until the End Phase, but other monsters you control cannot declare an attack this turn. If this card is sent to the Graveyard, you can Target 1 Machine-Type monster in your Graveyard: Discard 1 Machine-Type monster, and if you do, return the Target to the top of your deck.

[newhat]

This is a free permanent 300-ATK boost for any monster you Summon, since the Machine retype doesn't fade at the End Phase. If both players have a monster, it's a free 900+ boost to any monster you control.as long as it's your only attacker. It also lets you turn every monster ever into Chimeratech Fortress Dragon.

 

It would be helpful to have a permanent damage amp for a Machine Deck, but this isn't really a Machine card.

[Manpole]

I like this card and overall think the effects are fine and could fine use, but changing your opponents monsters all to machine to tribute for certain fusions can be a bit powerful. To keep the atk boost you can receive from having your opponents monsters be machines and to possibly negate effects that could help their non-machine monsters (solidarity, any field spell, ect), try changing the effect from "Once per turn treat all face-up monsters on the field to Machine..." to "During each of your Battle Phases treat all face-up monsters on the field as Machine..." or better yet, during either players battle phase?

 

So, I think the only problem with this card is the fusion summoning factor, other than that its great, including the artwork!