I've these web addresses:

index.php?area=guilds
index.php?area=guilds&page=create
index.php?area=guilds&page=view&name=The+Unit

Could I've only one rewrite rule with this in some way?

/guilds
/guilds/create
/guilds/view/The+Unit

Try these rules:

RewriteCond %{REQUEST_FILENAME} -f
RewriteRule ^ - [L]
RewriteRule ^[^/]+$ index.php?area=$0 [L]
RewriteRule ^([^/]+)/([^/]+)$ index.php?area=$1&page=$2 [L]
RewriteRule ^([^/]+)/([^/]+)/([^/]+)$ index.php?area=$1&page=$2&name=$3 [L]

The very first rule would be to avoid that Web addresses are rewritten that already could be planned for an existing file. Another rules reflect your three cases.

That one should work :

RewriteRule    /(.+)(?:/(.+))?(?:/(.+))?   index.php?area=$1&page=$2&name=$3