Swordfish

Swordfish is considered the best free to play healing tool, as it can heal 14 hitpoints per bite (other free to play foods heal more in total but less in one bite, plus it takes more time to eat twice than once). However, it is quite rare to be used in the wilderness, because of how difficult it is to fish swordfish when you get so much tuna in between. This can make it worth vastly more in large amounts, and thus lobsters are the preferred healing food of free to players.