Assassin's Creed IV: Black Flat At A Glance:

- Seamless land-sea combat shown

- Kenway's ship, the Jackdaw, is 'the second main character'

- Capturing rival crews and scavenging plays a big part

- Dynamic weather, multi-button combat and advanced stealth round out impressive showing.

Ubisoft has shown off a behind closed-doors demo of Ass Creed IV Black Flag, which thankfully went far better than the semi-disastrous Sony demo yesterday. Like Watch Dogs, the demo started with what we'd already seen: Kenway chasing down a mole in Blackbeard's organisation, stalking him and taking him down, before engaging in an explosive, naval battle which makes Errol Flynn's Captain Blood look like an arthritic tortoise. Turns out we didn't miss much at the end of Sony's conference, as the demo ended shortly after it crashed.

The second demo was dubbed 'the meat of the game' by Ubisoft. Set in the West Indies in 1777, it felt like Far Cry 3 mashed up with Ass Creed: diving off of towers into bright blue waters, climbing wooden encampments, and accepting contracts on the lives of various British. Most impressively the zoomed-out revealed that the previously impressive island we were on wasn't that big at all, showing how vast Black Flag is.

Again Ubisoft wanted to show off the seamless land to sea gamplay, with Kenway following a target from a dock to open water, via his ship the Jackdaw - what the dev team calls the 'second main character of the game'. Ship-destruction physics were demoed - shooting the sails slows the target boat, a broadside incapacitates it, before Kenway boards it, swinging in like a pirate Peter Parker.

Now on board - and surrounded by British redcoats - Ubi showed off the fighting mechanics, which now use all the face buttons again rather than the one button nonsense of Ass Creed III.

Once victorious you can recruit the crew, capture them, or scavenge the ship to repair any damages to your own vessel.

Speaking of scavenging, Kenway is shown swimming to recover sunken treasure from a shipwreck, acquiring a map that can be viewed - and used to mark objectives - on a tablet.

Dynamic weather made an appearance as Kenway sought said treasure, threatening the life of his crew and others: storm lighting strikes a British Navy vessel as they pass. Again, like in Watch Dogs, off-mission infiltration plays a big part - in one way to recover that lovely loot, in another to rescue pirates who can join your cause. Ubi was eager to show off a 'beauty shot' synchronisation - and it demonstrated just how much more engaging its world is, as opposed to the sterile Boston of before. The environment and mechanics on show are far better suited to the Ass Creed approach, and Black Flag is another impressive Ubisoft showing at this year's E3.