Seemed very good in the draft. But its concealer ability didn't become relevant, so it was effectively worse than Neurok Invisimancer. Even so, it might still be too good in limited.

2/1 unblockable for 3 with um... yeah, a complicated way to get it back that's not gonna matter in limited and you'll have better graveyard recursion (if you want it) out of limited.

Eh, it's a funky ability, and a 2/1 unblockable is pretty weak against any kind of pinging which you do have some of. How about it can only be unblockable if yuo have an instant card in your graveyard? That'll still be most of the time for blue, and it'll work with itself interestingly.

It does have the potential to power up Tarmoblast; and of course if you take the concealer ability off it breaks the cycle. I think it's OK, although conditional unblockable could work too.

I guess I could kill the black and blue concealer abilities, as they're fiddly and don't do very much, but leave the concealers in the colours that get permanents.

Used to be a Concealer with "1U: Ecriot Concealer becomes an instant card until end of turn. Activate this ability only when Ecriot Concealer is in your graveyard. (It's no longer a creature card this turn.)" This was too wordy and very hard to make relevant, so simplified to Vitenka's suggestion. The Concealer cycle was always different and less relevant on the blue and black elements, so removing them, which will also take down the complexity at common.