Lava style damage block hack
ONCE AGAIN... USE XKAS V.06 TO COMPILE...

Not a whole lot to say about this one... To use, set the tiles you want to have this effect to block type $02 ("Air. Fool X-RAY.") with a BTS value of $03. There are PLENTY of blank spaces in the lookup table that I mention, so take advantage if you want to add other blocks. Just add another DW $xxxx after the first one to point to new code. For example, $94:98B2's pointer corresponds to the BTS value of $03, and $94:98B4's pointer would correspond to the BTS value of $04.

Again, I suggest using the source file, not because it'll make you 1337 or cool or whatever, but because it'll give you a better idea of what's going on...and trust me, this hack is EXTREMELY simple. You'll be able to understand it with hardly any programming experience at all. Open up the source with notepad and at least look at it. (I think most browsers will open it up in a text viewer anyway) Plus, if you want to make one version of the block that does a little bit of damage and another that does a lot more, then all you need to do is add a few more lines. (There's room for 13 new blocks in that lookup table, and you can hack this a little more extensively to make even more.)

You could make some pools of acid or trenches filled with mustard gas or whatever you want if you used this in conjunction with some well drawn tiles.