In Forge, if you play Bell before Urborg, it doesn't effect all lands when Urborg comes into play and it's supposed to. I have tested this on both Android and PC.
613.8 Within a layer or sublayer, determining which order effects are applied in is sometimes done using a dependency system. If a dependency exists, it will override the timestamp system.
613.8a An effect is said to “depend on” another if (a) it’s applied in the same layer (and, if applicable, sublayer) as the other effect; (b) applying the other would change the text or the existence of the first effect, what it applies to, or what it does to any of the things it applies to; and (c) neither effect is from a characteristic-defining ability or both effects are from characteristic-defining abilities. Otherwise, the effect is considered to be independent of the other effect.
- Both are being applied in Layer 4.
- Urborg changes what Bell applies to.
- Both Urborg and Bell are CDAs.
- A kind of static ability that conveys information about an object’s characteristics that would normally be found elsewhere on that object (such as in its mana cost, type line, or power/toughness
box). See rule 604.3.- Urborg changes subtype, Bell changes P/T.
- A kind of static ability that conveys information about an object’s characteristics that would normally be found elsewhere on that object (such as in its mana cost, type line, or power/toughness