There are several of Playtech's Marvel slots here at Free Slots 24/7 and if I'm honest, the Blade slots are not the pick of the bunch. I prefer the Fantastic 4 game with it's innovative free spin feature or the more volatile but potentially rewarding 2nd installment of Iron Man but each to their own.
That all said, the graphics on Blade are pretty decent as they are with all the Marvel games. The gameplay, as is usual for Playtech, is also fairly innovative introducing the 'split symbol' concept on the 6th reel which effectively adds a paying symbol to a winning payline. It's like a cut-down version of IGT's split symbol concept found in Cats or Noah's Ark if you know those games.
The other decent feature is that in the free spins, the win multiplier goes up by one after each win, starting at 2x and maxing out at 5x. To be honest, the Blade slots have never really induced me to play enough to hit a massive win so maybe there's some Catch 22 in this: I can't actually say if big wins are that frequent on Blade so I'm afraid you'll have to play it to decide for yourself.
Other free slots featured here you might like are listed to the left: apart from the two I mentioned above you might also like to try the Marvel Daredevil slot or the low variance game, The Incredible Hulk which is good too.