Artifacts
MORE FIRE!
This is only niche playable at best. Direct damage is generall pretty bad in EDH. This does, however, nicely powerup Red's damage based sweepers - Blasphemous Act now kills Worldspine Wurm, for instance, and this effectively gives you a two-mana discount on spells like Starstorm and Earthquake.
It also makes various Chandras suck less.
Seems kinda narrow, until you realize "Enters the battlefield effects" are triggered abilities. As are a great number of other effects you probably never realized were triggered abilities.
In short, this copies a TON of effects. So it'll definitely get played... like, a lot.
That said, I don't think it's quite as absurd as some of the hype suggests. It'll be a solid value engine at best.
Costs 4, Equip 4, all it gives is +4/+4? Nah. I don't particularly like this. I mean, from a flavor/design standpoint, it's pretty awesome. Suit of armor that comes to life - a classic trope well executed in card form!
Power level, though, is just weaksauce.
I've actually considered this for my Savra deck, but I already ahve Disciple of Griselbrand. Not sure it's any good anywhere else though.
Planar Portal is just way too slow and clunky these days. Most decks just don't have time to spend this much mana just to tutor, and cards like this get Krosan Gripped SO fast it'll make your head spin. That said, I think this will get played quite a bit. Sharrum decks, for example can A) make the absurd mana needed to fuel it, B) recur it after it's spent, and C) have combo peices worth spending infinity mana to go find.
Me? I like the art quite a lot, but I'm yawning at the card itself.
If this were Indestructible, I think it'd be really playable. But as-is, I can't think of many decks that want to play something like this, at least at this cost. I mean, Pelakka Wurm is a 7/7 Trample with TWO all-upside effects attached, and it still doesn't get played. This is a good deal worse than Pelakka Wurm.
In a format where Wasteland, Strip Mine, Ghost Quarter
and every Green/Red/Black land destruction spell ever printed already exist, I would actually be embarrased to be seen using this. I mean, really?