Replace to slime

A lot of players want spleef. A lot of players like trapping. Whilst it is possible to make a spleef custom server, I think this suggestion could also make Sky wars even more fun.
A new block called “Spleefer” could turn a 5x5 square in front of the player to slime. This could be a wall placed in front of you that offers a temporary protection for non-PC players who can’t spam blocks as easily or can be placed on the floor and turn it to slime to either spleef players or save you fall.