This doesn't cover every potentially advantageous trade, but here are some of the more useful things to aim for. Where possible, all chains start from items that can be purchased or obtained in unlimited quantity from monsters.

If you chose the Ragnarök sword instead of the magicite, the only reason not to trade up for the Lightbringer is that the latter's randomly cast Holy can become a liability in some situations, unlike the former's Flare. Other than that, the Lightbringer does everything the Ragnarök does, plus has a perfect hit rate, ignores row, and provides an additional 4 agility and 20 MEvd (and 20 evade).

Good for both wielding and throwing. You can also get them from the Holy Dragon when it reappears on the Beast Plain, but this way may be more reliable than a rare steal from an infrequent encounter.

Might as well upgrade that blade you won on the Mystic Continent, right? You can also steal extra Murasame blades from Kamuy in Gogo's cave if you're lucky.

And another upgrade for Cayenne's weaponry. Extra Masamune blades can be stolen from Bodyguard in the final dungeon, if you don't want to start from the Murasame. This is also quite good for throwing, though Sa Gojō's Spear is better.

The Wizard Rod is a great weapon for all three characters who can use it, but there's only one available normally. The game has two Heal Rods, though, and did you really need both?

Though not the most powerful throwing weapons available in unlimited quantity, Kazaguruma are still potent projectiles. You can buy Fuuma Shuriken, so supply is not an issue.

The Bone Club itself is useless except as part of a wagering chain, but some people like to fill out their inventories, and this is a straightforward way to get one, using a buyable item.

A powerful but fragile weapon only obtainable in the coliseum or by morphing certain enemies. All three elemental swords are for sale in the WoR, so it's easy enough to get them.

Since both the Falchion and the Crystal Mail are available in stores, there's no reason not to have a full set of these once you can beat the enemies faced.

The Flame Shield's icy counterpart. Both are invaluable when facing certain opponents, but do be careful since each also carries a weakness.

Superior in defense to the Flame and Ice Shields, and lacking any weakness, the Thundergod's Shield works well in any situation. Genji's Bracers can be stolen from Dragons with a little luck. You could also wager Gauntlets instead, but there are only a few of those in the game.

While it lacks any elemental defenses, Genji's Shield has the best stats of any shield you can get in unlimited quantity, and anyone (except Umaro) can use it. You can also steal Thundergod's Shields from Muud Suud in the final dungeon if that seems like less trouble than amassing Genji's Bracers.

The game's best headgear, though unfortunately only Relm can use it. If necessary, you can use a Carapace Shield to get a Dish and an Armor Kappa to get a Carapace Shield.

The Crown of Thorns isn't easy to come by, being primarily obtained as a rare steal from Hidden or by morphing certain enemies, but this is the only way to get a Mirage Vest.

At least those Bone Clubs are useful for something. The Red Jacket isn't great, but it's not bad either, and if nothing else, it's Mash's best armor.

The top armor stat-wise for many fighters. Steal from nearly anything in Auzer's mansion for more suits.

If you spent some time on the Beast Plain after beating King Behemoth, you should be drowning in Behemoth Suits. Trade in a few to get godly protection for Gau and Mog. Joined with some other powerful equipment, it lets them laugh off any physical damage that doesn't ignore defense.

The Wyvern's Horn in the Phoenix Cave is the only one you'll ever find without fighting in the coliseum. Get a few extras if you like to Jump.

Combining four beneficial status effects in a single accessory can come in handy. The only downside I'm aware of is that 'regenerate' status can throw off the delaying effect of certain instant-death effects.

In case you feel like power leveling, this is probably the best way to get extras of the double experience accessory.

Steal extra Protective Bracelets from Dragonfiends in the final dungeon. Also note that the prize for wagering a Brave Ring is a Protective Bracelet, so you can swap them back and forth if you want, but the Miracle Shoes also obtained here are generally superior to the bracelet.

Some of the game's more unusual equipment leads to this accessory that allows any character (except Umaro) to use nearly any equipment. It's particularly useful for Gau, since he's normally without a weapon but can easily reach maximum attack power with one, and many special weapon effects combine with and gain benefit from Rage special attacks. The Kazekiri Blade often works well.

Mostly useful for further wagering, but you can play around with name changes if you like.

Or any of many other items. Those listed are the cheapest if you feel like challenging Typhon for an Elixir. Whether it's worth the effort and frustration is debatable. Go all-out offense if you try it.

If you like randomness, or don't have the Ragnarök magicite but want to try for an outside chance of morphing enemies anyway, these are for you.