Very nice. Reminds me of Hunted Wumpus or Iwamori of the Open Fist (also Boldwyr Heavyweights), but this is even more interactive. Even if defender has a 6/6 in hand, I could see blocking the first attack of this on a Kitchen Finks or Nekrataal or something, just in the hope of getting a second free creature out of the deal.

Just to point out a minor flaw in this card...

­
Creature - Orc
Defender
4/4

Seems inappropriately strong compared to Ogre Sentry. I think you want a line in there about 'can't block' or 'must attack'.

This card is unprecedented in attempting to have a creature become blocked while it's still the declare attackers step--note that even Flash Foliage got errata to stop that as soon as it was pointed out. Unlike Flash Foliage, the timing of this ability doesn't work any other way, so changing it to be in line with the rest of the game won't be so easy.

"Whenever ~ attacks, defending player may put a creature card from their hand onto the battlefield. That creature blocks ~ this turn if able."

@dude I wanna keep the force blocking. I don't want it to be skirted by some evasive aura.

"At the beginning of the declare blockers step, if ~ is attacking, the defending player may put a creature from their hand onto the battlefield blocking it." How's that?

dude's version sounds good.

If you're fixing typos, by the way, the word "Neighbourhood" is rather impressively typoed in this card's name...

New wording is more sensical to the average player than "declare blockers step".