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Just a little correction about DMA.
DMA stands for Direct Memory Access, and is used when performing IO to a hard disk or a CD-ROM, for example. Without DMA, in PIO mode, the CPU is used a lot because it's reading the bytes from the IO ports of the device and writing them to the memory locations, or vice-versa. With DMA, or Ultra-DMA, data is read from the device and placed in memory directly (by the DMA controller), while the CPU is doing something else, or is idle.
DMA can also be used in a sound card for example. In that case, the sound card goes directly to memory to read the sound samples, the CPU doesn't have to be in the middle instead of doing something else.
The dynamically allocated memory you're talking about is a simple malloc(), or a VirtualAlloc call, which reserve a memory region in the heap and return a pointer to it.
Also, regarding item 2, "base address", I'd say that probably it's likely that a single pointer won't suffice. Due to the chaining of objects created at runtime, you may have a static location which points to a structure that can be in different locations. That structure, in turn, will contain one pointer for another structrure, and so on, until another structure some levels deeper will contain the actual lives and energy counters.
That said, this 2nd approach will also hardly work on a newer version. Both the initial base address, and the structure's offsets may change between versions.
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