Items and abilities
Over the quest of your project, you may come to points where the characters gain new items, spells, abilities, etc. You DON'T make a new set of (sometimes dozens of) pages for each such item, especially if you plan to make it so that adventurers may gain them in different orders. Having 30 pages with 4 items in any order means making up to 30*2^4 pages. That's gonna take WAY too long and in any case you won't finish.
Instead, make it ingenious. Or, use this approach:
Use the search engine (such as the one in the sidebar). You can include a search-box into your page using Template:Searchbox. This works especially well if you're working with things involving knowledge, such as spells, facts, and procedures. The adventurer puts the "password" into the search engine, along with information about the page itself, into the engine, and hits enter to go to that page. Only if the combination is correct do they go to that page. (Otherwise, they encounter a "page not created" error.) Items can be handled by using the name of the item, or the name of the action used with the item.
For example, if the instance occurs on page "X", and the action is "Y", you could have the quest continue on the page "X/Y" or "XYX", whatever (redirecting to a better title if necessary). Play around with this concept! Don't make it too predictable for adventurers, since they can use the search engine to find articles with those passwords in them without necessarily having to know the correct combination. (If you keep the passwords short then the search engine will run into a Lot of results and adventurers will be discouraged from trying them out, but if you use the /Y method as described earlier it will be painfully obvious.)