This is monster farmer, my RPG. What I've done so far, is built a well structured hex grid turn-based combat engine. The game is intended to be very combat orientated, with no plot.
Concept
The idea is as follows. Capture and raise creatures by roaming locations and battling more random monsters. Sounds like Pokemon (GRR!), but there are differences. Instead of a storyline and quests, with pages of NPC dialogue, there is a central arena. The rest of the game world will purely be terrain based (with trees etc) randomised combat. Upon entering the arena with your monsters, you will be connected to the main server, providing nothing more but a lobby (the simple functions used by my now deceased online survival horror will enable this). When you select your opponent, it goes into the typical turn based peer to peer combat. Winner gains rating, loser loses it etc like multiplayer flash game sites. This system removes the need for towns full of NPCs and a storyline, replacing it with the goal to be the best trainer with the highest rating!
As for combat, its gonna be pretty simple. Simple hex grid based combat; a cross between Final Fantasy Tactics and Pokemon (but a hex grid as its better than square based for 3D). Simple combat based on simple stats like Attack, Defence, Agility and Speed. Another change is that your human character will be in the battle (along with say 4 monsters per side). This adds tactics that you may attack the trainer rather than the monsters, causing the opponent to lose. The trainer will be fairly durable (to prevent this), but will have only a few options: melee attack, use item and capture. To use these, the player must be adjacent to the target (meaning you cant run in for the capture too soon as failure leaves you vulnarable to attack). This also means that to use items (such as a healing leaf) on a monster, you must run up next to them and use it.
Now for some screenshots of the engine so far...
Simple... yet fun!